System and method for providing access to replicated data

• US 8,103,625 B1
• Filed: 04/28/2008
• Issued: 01/24/2012
• Est. Priority Date: 12/17/2002
• Status: Expired due to Fees

• Current Assignee: Veritas Technologies, LLC (Whitehouse Group Ltd.)
• Original Assignee: Symantec Operating Corporation (Gen Digital Inc.)
• Inventors: Pandit, Bhushan S.
• Primary Examiner(s): Hwa, Shyue Jiunn
• Application Number:
  US12/110,500
• Time in Patent Office: 1,366 Days
• Field of Search: None
• US Class Current: 707/610
• CPC Class Codes: G06F 16/184 implemented as replicated file system
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users

Abstract

A system and method for providing access to replicated data is disclosed. Embodiments of the present invention utilize a remote access file system to provide access to replicated data concurrently with replication. According to one embodiment including unidirectional replication, access to a replicated target volume is provided using a remote access file system to perform reads locally or “directly” and to perform writes indirectly to a replication source volume which are subsequently replicated to the replication target volume. According to another embodiment, bi-directional replication is provided and access to both replication source and replication target volumes are provided locally and subsequently replicated as necessary.

Claims

1. A method comprising:

replicating data between a first volume and a second volume, wherein

said replicating is performed in response to storage of said data,

said replicating creates a replicated copy of said data,

said replicating is bi-directional between said first volume and said second volume,

said first volume is associated with a first node,

said second volume is associated with a second node, and

said replicating facilitates

bi-directionally replicating said data between said first node and said second node; and

providing access to said replicated copy of said data, wherein

said access is provided concurrently with said replicating,

said access is provided utilizing a remote access file system,

said access is provided via a remote access file system client,

said remote access file system client is local to a one of said first volume and said second volume,

said providing comprises

arbitrating said access,

said arbitrating said access comprises

arbitrating access to said data by establishing a resource lock for said data,

said arbitrating is performed by a remote access file system server, and

said remote access file system server is local to another of said first volume and said second volume.

2. The method of claim 1, wherein

said replicating further comprises

replicating said data from said first node to said second node.

3. The method of claim 1, wherein said providing comprises:

receiving an access request for said replicated copy of said data utilizing a remote access file system client local to said second node, and

arbitrating access to said data utilizing a remote access file system server local to said first node in response to said receiving said access request.

4. The method of claim 3, wherein said providing further comprises:

maintaining file system data at said second node utilizing said remote access file system.

5. The method of claim 3, wherein said receiving comprises:

receiving said access request from an application local to said second node.

6. The method of claim 3, wherein

said arbitrating said access to said data is performed at a file level.

7. The method of claim 3, wherein

said establishing is performed utilizing said remote access file system server.

8. The method of claim 3, wherein said receiving comprises:

receiving a read request for said replicated copy of said data.

9. The method of claim 3, wherein said receiving comprises:

receiving a write request for said replicated copy of said data.

10. The method of claim 9, wherein said providing further comprises:

performing a write operation on said data within said first volume utilizing said remote access file system, in response to receiving said write request for said replicated copy of said data, wherein

said replicating is performed in response to said performing said write operation.

11. A computer program product comprising:

a first set of instructions, executable on a computer system, configured to replicate data between a first volume and a second volume, wherein

said first set of instructions are executed in response to storage of said data, and

said first set of instructions comprise

a first sub-set of instructions, executable on said computer system, configured to create a replicated copy of said data,

said first set of instructions is configured to perform said replication bi-directionally between said first volume and said second volume,

said first volume is associated with a first node,

said second volume is associated with a second node, and

said first set of instructions is further configured to bi-directionally replicate said data between said first node and said second node;

a second set of instructions, executable on said computer system, configured to provide access to said replicated copy of said data, wherein

said access is provided to said replicated copy of said data in said second volume concurrently with said replicating,

said access is provided to said replicated copy of said data in said second volume utilizing a remote access file system,

said access is provided via a remote access file system client,

said remote access file system client is local to said second volume,

said second set of instructions comprises

a second sub-set of instructions, executable on said computer system, configured to arbitrate said access,

said second sub-set of instructions are configured to arbitrate said access by virtue of being configured to establish a resource lock for said data,

said second sub-set of instructions are configured to be executed by a remote access file system server, and

said remote access file system server is local to said first volume; and

a computer-readable storage medium, wherein said computer program product is encoded in said computer-readable storage medium.

12. The computer program product of claim 11, wherein

said first set of instructions further comprises

a second subset of instructions, executable on said computer system, configured to replicate said data from said first node to said second node.

13. The computer program product of claim 12, wherein said second set of instructions comprises:

a first subset of instructions, executable on said computer system, configured to receive an access request for said replicated copy of said data utilizing a remote access file system client local to said second node; and

a second subset of instructions, executable on said computer system, configured to arbitrate access to said data utilizing a remote access file system server local to said first node, wherein said second subset of instructions are executed in response to receipt of said access request.

14. The computer program product of claim 13, wherein said first subset of instructions said second set of instructions comprises:

a first subsubset of instructions, executable on said computer system, configured to receive said access request from an application local to said second node.

15. The computer program product of claim 13, wherein said second subset of instructions said second set of instructions comprises:

said second sub-set of instructions are further configured to arbitrate said access to said data at a file level.

16. The computer program product of claim 13, wherein said first subset of instructions said second set of instructions comprises:

a first subsubset of instructions, executable on said computer system, configured to receive a read request for said replicated copy of said data; and

a second subsubset of instructions, executable on said computer system, configured to receive a write request for said replicated copy of said data.

17. The computer program product of claim 16, wherein said first subset of instructions said second set of instructions further comprises:

a first subsubset of instructions, executable on said computer system, configured to perform a write operation on said data within said first volume utilizing said remote access file system in response to receiving said write request for said replicated copy of said data; and

a second subsubset of instructions, executable on said computer system, configured to replicate said data from said first volume to said second volume in response to said performing.

18. An apparatus comprising:

means for replicating data between a first volume and a second volume, wherein

said means for replicating is responsive to storage of said data, and

said means for replicating is configured to create a replicated copy of said data;

said means for replicating is configured to replicate said data bi-directionally between said first volume and said second volume,

said first volume is associated with a first node,

said second volume is associated with a second node, and

said means for replicating facilitates

bi-directionally replicating said data between said first node and said second node; and

a remote access file system, wherein

said remote access file system is configured to provide access to said replicated copy of said data,

said remote access file system comprises

a remote access file system client, and

a remote access file system server,

said remote access file system server is local to said first volume, and

said remote access file system client is local to said second volume; and

means for providing access to said replicated copy of said data in said second volume, wherein

said means for providing said access is configured to provide said access concurrently with replicating said data,

said means for providing said access is further configured to provide said access utilizing said remote access file system,

said access is provided via said remote access file system client,

said remote access file system server comprises

means for arbitrating said access, and

said means for arbitrating said access comprises

means for establishing a resource lock for said replicated copy of said data.

19. The apparatus of claim 18, wherein

said means for replicating further comprises

means for replicating said data from said first node to said second node,

said means for providing comprises

means for receiving an access request, wherein

said access request is a request for said replicated copy of said data,

said means for receiving is configured to utilize a remote access file system client,

said remote access file system client is local to said second node,

said means for arbitrating said access is configured to utilize a remote access file system server, and

said remote access file system server is local to said first node, and

said means for arbitrating access is responsive to receipt of said access request.