Customizing a namespace in a decentralized storage environment

• US 20060271598A1
• Filed: 03/31/2006
• Published: 11/30/2006
• Est. Priority Date: 04/23/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Systems, Inc.
• Inventors: Wong, Thomas K., Simpkins, Richard A., Tsirigotis, Panagiotis, Iyengar, Anand, Wong, Chi Ming, Chan, Yu Cheong
• Granted Patent: US 8,190,741 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/119 Details of migration of file systems migration mechanisms in storage systems G06F3/0647
• CPC Class Codes: G06F 16/184 implemented as replicated file system

Abstract

Systems and methods to customize a namespace using a synthetic namespace. A NAS switch provides file migrations in a NAS storage network that are transparent to the clients. The NAS switch file handles are used to customize a namespace. More specifically, a synthetic namespace is generated from one or more file location tables that map the switch file handles to NAS file handles. The NAS file handles are independent of a physical export containing the objects referred to by the NAS file handles. In one example, the synthetic namespace presents a home directory corresponding to a location of a user.

Claims

1. A computer-implemented method for customizing a namespace in a storage network, comprising:

receiving at least one of NAS (Network Attached Storage) file handles and path names from one or more exported physical shares, the NAS file handles and path names indicative of locations of objects on the file shares;

maintaining one or more file location tables that map switch file handles to the NAS file handles and path names, the switch file handles being independent of the object locations, the file location table configured in accordance with a synthetic namespace of selected objects that are available to the one or more clients independent of the one or more exported physical shares, and

providing a switch file handle to the one or more clients, the switch file handle designating the file location table.

2. The method of claim 1, further comprising:

maintaining a second file location configured in accordance with a second synthetic namespace of selected objects that are available to a second one or more clients.

3. The method of claim 1, wherein the object comprises a file.

4. The method of claim 1, wherein the object comprises a directory having objects representative of sub-directories and files.

5. The method of claim 1, further comprising:

receiving a request to access to an object;

identifying a user associated with the request; and

forwarding the request to a file location table based on the user.

6. The method of claim 5, further comprising:

identifying at least one of a NAS file handle and path name in the file location table that is associated with the switch file handle;

forwarding the request to the object location associated with the at least one of NAS file handle and path name.

7. The method of claim 6, further comprising:

responsive to not identifying at least one of a NAS file handle and path name associated with the request;

forwarding the request to a file location table based on the physical share associated with the request.

8. The method of claim 5, further comprising:

responsive to not identifying a user associated with the request;

forwarding the request to a file location table based on the physical share associated with the request.

9. A computer-implemented method for customizing a namespace in a storage network, comprising:

receiving location-based pointers from one or more exported physical shares, the file handles including locations of objects on the file shares;

maintaining one or more file handle migration tables that map switch file handles to the location-based pointers, the switch file handles being independent of the object locations, a portion of entries in the file handle migration table configured in accordance with a synthetic namespace of selected objects that are available to the one or more clients independent of the one or more exported physical shares, and portion of entries in the file handle migration table configured to track objects that change locations; and

providing a switch file handle to the one or more clients, the switch file handle designating the file location table.

10. A computer program product, comprising a computer-readable medium having computer program instructions and data embodied thereon for customizing a namespace in a storage network, the method comprising:

receiving at least one of NAS (Network Attached Storage) file handles and path names from one or more exported physical shares, the NAS file handles and path names indicative of locations of objects on the file shares;

maintaining one or more file location tables that map switch file handles to the NAS file handles and path names, the switch file handles being independent of the object locations, the file location table configured in accordance with a synthetic namespace of selected objects that are available to the one or more clients independent of the one or more exported physical shares, and

providing a switch file handle to the one or more clients, the switch file handle designating the file location table.

11. The computer program product of claim 10, further comprising:

maintaining a second file location configured in accordance with a second synthetic namespace of selected objects that are available to a second one or more clients.

12. The computer program product of claim 10, wherein the object comprises a file.

13. The computer program product of claim 10, wherein the object comprises a directory having objects representative of sub-directories and files.

14. The computer program product of claim 10, further comprising:

receiving a request to access to an object;

identifying a user associated with the request; and

forwarding the request to a file location table based on the user.

15. The computer program product of claim 14, further comprising:

identifying at least one of a NAS file handle and a path name in the file location table that is associated with the switch file handle;

forwarding the request to the object location associated with the at least one of NAS file handle and path name.

16. The computer program product of claim 15, further comprising:

responsive to not identifying at least one of a NAS file handle and path name associated with the request;

forwarding the request to a file location table based on the physical share associated with the request.

17. The computer program product of claim 14, further comprising:

responsive to not identifying a user associated with the request;

forwarding the request to a file location table based on the physical share associated with the request.

18. A system for customizing a namespace in a storage network, comprising:

a file server module to receive NAS (Network Attached Storage) file handles from one or more exported physical shares, the NAS file handles including locations of objects on the file shares;

a synthetic namespace module to maintain one or more file location tables that map switch file handles to NAS file handles, the switch file handles being independent of the object locations, the file location table configured in accordance with a synthetic namespace of selected objects that are available to the one or more clients independent of the one or more exported physical shares, and

a client server module, coupled in communication with the file server module and the synthetic namespace module, the client server module configured to provide a switch file handle to the one or more clients, the switch file handle designating the file location table.