Mechanism to provide direct multi-node file system access to files on a single-node storage stack

• US 7,191,225 B1
• Filed: 11/27/2002
• Issued: 03/13/2007
• Est. Priority Date: 11/27/2002
• Status: Active Grant

• Current Assignee: Veritas Technologies, LLC (Whitehouse Group Ltd.)
• Original Assignee: Veritas Operating Corporation (Gen Digital Inc.)
• Inventors: Borthakur, Dhrubajyoti
• Primary Examiner(s): Tran; Philip B.
• Application Number:
  US10/306,562
• Time in Patent Office: 1,567 Days
• Field of Search: 709/213, 709/214, 709217-219, 709/225, 709/229, 709/248, 707/8, 707/10, 711/114, 711/147, 711/154
• US Class Current: 709/213
• CPC Class Codes: G06F 16/10 File systems; File servers
• CPC Class Codes: Y10S 707/99938 Concurrency, e.g. lock management in shared database

Abstract

A method and system for providing multi-node file system access to files on a single-node storage stack. The method may include sending a data access request from a client system to a server system over a network. The data access request may comprise a request to access data which is stored on one or more storage devices whose access is controlled by the server system. The method may include using a mapping interface to determine a quantity of components in the storage stack. The method may further include using the mapping interface to communicate with the storage stack components to retrieve a physical location of the data on the storage devices and sending the physical location of the data to the client. The method may include the client bypassing the server to access the data on the storage devices at the physical location provided by the mapping interface.

Claims

1. A method comprising:

sending a data access request from a first computer system to a second computer system, wherein the second computer system is operable to control access to one or more storage devices, wherein the second computer system comprises a storage stack comprising components for managing the one or more storage devices, and wherein the data access request comprises a request to access data which is stored on the one or more storage devices;

using a mapping interface on the second computer system to determine a quantity of components in the storage stack;

using the mapping interface on the second computer system to communicate with the components in the storage stack to retrieve a physical location of the data on the one or more storage devices;

sending the physical location from the second computer system to the first computer system; and

the first computer system bypassing the second computer system to access the data on the one or more storage devices at the physical location.

2. The method of claim 1,

wherein using the mapping interface on the second computer system to retrieve the physical location comprises:

inputting the data access request to the mapping interface to retrieve a logical location of the data from a file system on the second computer system;

inputting the logical location to the mapping interface to retrieve a block map from a volume manager on the second computer system; and

inputting the block map to the mapping interface to retrieve the physical location of the data from one or more device drivers on the second computer system.

3. The method of claim 1,

wherein using the mapping interface on the second computer system to retrieve the physical location comprises:

inputting the data access request to the mapping interface to retrieve a logical location of the data; and

inputting the logical location to the mapping interface to retrieve the physical location of the data from one or more device drivers for the one or more storage devices.

4. The method of claim 1,

wherein the storage stack on the second computer system comprises a single-node storage stack.

5. The method of claim 1,

wherein the data comprises a file which is stored across two or more of the storage devices.

6. The method of claim 1,

wherein, in sending the data access request to the second computer system, the first computer system is operable to send the data access request over a first network;

wherein, in accessing the data on the one or more storage devices at the physical location, the first computer system is operable to access the data over a second network.

7. The method of claim 1,

wherein the one or more storage devices are configured as a RAID with byte-level data striping, and wherein the data accessed by the first computer system is striped.

8. The method of claim 1,

wherein the one or more storage devices are configured to use data mirroring, and wherein the data accessed by the first computer system is mirrored.

9. A computer-readable storage medium comprising program instructions, wherein the program instructions are computer-executable to implement:

receiving a data access request at a second computer system from a first computer system, wherein the second computer system is operable to control access to one or more storage devices on a storage area network, wherein the second computer system comprises a storage stack comprising components for managing the one or more storage devices, and wherein the data access request comprises a request to access data which is stored on the one or more storage devices;

using a mapping interface on the second computer system to determine a quantity of components in the storage stack;

using the mapping interface on the second computer system to communicate with the components in the storage stack to retrieve a physical location of the data on the one or more storage devices;

sending the physical location from the second computer system to the first computer system; and

wherein the first computer system is operable to bypass the second computer system to access the data on the one or more storage devices at the physical location.

10. The computer-readable storage medium of claim 9,

wherein using the mapping interface on the second computer system to retrieve the physical location comprises:

inputting the data access request to the mapping interface to retrieve a logical location of the data from a file system on the second computer system;

inputting the logical location to the mapping interface to retrieve a block map from a volume manager on the second computer system; and

inputting the block map to the mapping interface to retrieve the physical location of the data from one or more device drivers on the second computer system.

11. The computer-readable storage medium of claim 9,

wherein using the mapping interface on the second computer system to retrieve the physical location comprises:

inputting the data access request to the mapping interface to retrieve a logical location of the data; and

inputting the logical location to the mapping interface to retrieve the physical location of the data from one or more device drivers for the one or more storage devices.

12. The computer-readable storage medium of claim 9,

wherein the data comprises a file which is stored across two or more of the storage devices.

13. The computer-readable storage medium of claim 9,

wherein the one or more storage devices are configured as a RAID with byte-level data striping, and wherein the data accessed by the first computer system is striped.

14. A system, comprising:

a processor;

one or more storage devices;

a storage stack comprising components for managing the one or more storage devices; and

a memory comprising program instructions, wherein the program instructions are executable by the processor to;

control access to the one or more storage devices;

receive a data access request from a client computer system, wherein the data access request comprises a request to access data which is stored on the one or more storage devices;

use a mapping interface to determine a quantity of components in the storage stack;

use the mapping interface to communicate with the components in the storage stack to retrieve a physical location of the data on the one or more storage devices;

send the physical location to the client computer system; and

wherein the client computer system is operable to bypass the processor to access the data on the one or more storage devices at the physical location.

15. The system of claim 14,

wherein, to use the mapping interface to retrieve the physical location, the program instructions are executable by the processor to:

input the data access request to the mapping interface to retrieve a logical location of the data from a file system;

input the logical location to the mapping interface to retrieve a block map from a volume manager; and

input the block map to the mapping interface to retrieve the physical location of the data from one or more device drivers for the one or more storage devices.

16. The system of claim 14,

wherein, to use the mapping interface to retrieve the physical location, the program instructions are executable by the processor to:

input the data access request to the mapping interface to retrieve a logical location of the data; and

input the logical location to the mapping interface to retrieve the physical location of the data from one or more device drivers for the one or more storage devices.

17. The system of claim 14,

wherein the data comprises a file which is stored across two or more of the storage devices.

18. The system of claim 14,

wherein the one or more storage devices are configured as a RAID with byte-level data striping, and wherein the data accessed by the client computer system is striped.

19. A system comprising:

means for sending a data access request from a first computer system to a second computer system, wherein the second computer system is operable to control access to one or more storage devices, wherein the second computer system comprises a storage stack comprising components for managing the one or more storage devices, and wherein the data access request comprises a request to access data which is stored on the one or more storage devices;

means for using a mapping interface on the second computer system to determine a quantity of components in the storage stack;

means for using the mapping interface on the second computer system to communicate with the components in the storage stack to retrieve a physical location of the data on the one or more storage devices;

means for sending the physical location from the second computer system to the first computer system; and

wherein the first computer system is operable to bypass the second computer system to access the data on the one or more storage devices at the physical location.

20. The system of claim 19,

wherein the means for using the mapping interface on the second computer system to retrieve the physical location comprise:

means for inputting the data access request to the mapping interface to retrieve a logical location of the data; and

means for inputting the logical location to the mapping interface to retrieve the physical location of the data from one or more device drivers for the one or more storage devices.