Apparatus and method for tandem operation in a storage network

• US 7,191,290 B1
• Filed: 04/25/2003
• Issued: 03/13/2007
• Est. Priority Date: 09/16/2002
• Status: Expired due to Fees

• Current Assignee: Network Appliance Incorporated (NetApp, Inc.)
• Original Assignee: Network Appliance Incorporated (NetApp, Inc.)
• Inventors: Amdur, Matthew B., Ayyar, Kartik, Prakash, Ashish, Ackaouy, Emmanuel
• Primary Examiner(s): Choi; Woo H.
• Application Number:
  US10/424,142
• Time in Patent Office: 1,418 Days
• Field of Search: 709/213, 709/219, 709/225, 711/919, 714/4
• US Class Current: 711/119
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: H04L 67/5682 Policies or rules for updating, deleting or replacing the stored data

Abstract

In one embodiment, a method of processing data in a network with multiple proxy caches, includes: pushing cached data in a first proxy cache to at least one other proxy cache in a cluster configuration; caching the data from the first proxy cache; and permitting a client to access the data in the at least one other proxy cache in the cluster configuration. In another embodiment, a method of processing data in a network with multiple proxy caches, includes: providing a snapshot replica from a first server to second server; and permitting a proxy cache to access the second server for data in the snapshot replica, in response to a disconnect operation of the first server.

Claims

1. A method of processing data in a network with multiple proxy caches, the method comprising:

defining a cluster configuration including a first proxy cache and a second proxy cache, where the cluster configuration designates the second proxy cache to receive cached data from the first proxy cache, wherein each of the first and second proxy caches includes an associated group member module that defines the cluster configuration;

pushing cached data in the first proxy cache to the second proxy cache in the cluster configuration;

caching, by the second proxy cache, the data from the first proxy cache; and

permitting a client to access the data in the second proxy cache in the cluster configuration.

2. The method of claim 1, wherein the data is cached in the second proxy cache for a minimum time period.

3. The method of claim 1, further comprising:

in response to a client access request, directing the request to one of the proxy caches in the cluster configuration to achieve load balancing.

4. The method of claim 1, wherein the cached data pushed to the second proxy cache is a frequently requested data.

5. The method of claim 1, further comprising:

performing a fail-over from the first proxy cache to the second proxy cache in the cluster configuration, in response to failure of the first proxy cache.

6. The method of claim 5, wherein the second proxy cache receives request from a client after the fail-over to the second proxy cache is performed.

7. The method of claim 6, wherein the second proxy cache can send the cached data to the client in response to the request from the client.

8. The method of claim 1, wherein the first proxy cache can transmit cached data to a requesting client.

9. The method of claim 1, wherein the second proxy cache in the cluster configuration can transmit the cached data to a requesting client.

10. The method of claim 1, wherein the second proxy cache is prevented from transmitting the cached data to a requesting client for a designated time period.

11. The method of claim 1, wherein the first proxy cache and the second proxy cache can receive a write request from a client to modify the cached data and to send the modified cached data to a server.

12. The method of claim 1, wherein the first proxy cache includes a first control manager module, wherein the second proxy cache includes second control manager module, and wherein the first and second control manager modules set a schedule for transmitting the cached data from the first proxy cache to the second proxy cache.

13. The method of claim 1, wherein the first proxy cache includes a first control manager module, wherein the second proxy cache includes second control manager module, and wherein the first and second control manager modules designates the second proxy cache to receive cached data from the first proxy cache and prevent other proxy caches from receiving the cached data.

14. The method of claim 1, wherein the first proxy cache includes a group leader module, wherein the second proxy cache includes group member module, and wherein the group leader module coordinates with the group member module so that the cached data is sent from the first proxy cache to the second proxy cache and so that other proxy caches are prevented from receiving the cached data.

15. The method of claim 1, wherein the first proxy cache includes a group member module, wherein the second proxy cache includes second group member module, and wherein the first and second group member modules configure the first proxy cache and the first proxy cache as belonging to the cluster configuration.

16. The method of claim 1, further comprising:

placing a timeout header in the cached data, where the timeout header sets a timeout time period when the cached data is eligible for flushing from the second proxy cache.

17. The method of claim 1, further comprising:

placing a minimum age header in the cached data, where the minimum age header sets an aged time period when the cached data is eligible to be served by the second proxy cache to a requesting client.

18. An apparatus for processing data in a network with multiple proxy caches, the apparatus comprising:

a cluster configuration including a first proxy cache and a second proxy cache, where the cluster configuration designates the second proxy cache to receive cached data from the first proxy cache, wherein each of the first and second proxy caches includes an associated group member module that defines the cluster configuration;

wherein the first proxy cache is configured to push cached data to the second proxy cache in the cluster configuration;

wherein the second proxy cache is configured to cache the data from the first proxy cache; and

wherein the first proxy cache and the second proxy cache permits a client to access the cached data.

19. The apparatus of claim 18, wherein the data is cached in the second proxy cache for a minimum time period.

20. The apparatus of claim 18, further comprising:

a load balancing switch configured to direct a client access request to one of the proxy caches in the cluster configuration to achieve load balancing in response to the client access request.

21. The apparatus of claim 18, wherein the cached data pushed to the second proxy cache is a frequently requested data.

22. The apparatus of claim 18, wherein fail-over from the first proxy cache to second proxy cache in the cluster configuration is performed, in response to failure of the first proxy cache.

23. The apparatus of claim 22, wherein the second proxy cache receives request from a client after the fail-over to the second proxy cache is performed.

24. The apparatus of claim 23, wherein the second proxy cache can send the cached data to the client in response to the request from the client.

25. The apparatus of claim 18, wherein the first proxy cache can transmit cached data to a requesting client.

26. The apparatus of claim 18, wherein the second proxy cache in the cluster configuration can transmit the cached data to a requesting client.

27. The apparatus of claim 18, wherein the second proxy cache is prevented from transmitting the cached data to a requesting client for a designated time period.

28. The apparatus of claim 18, wherein the first proxy cache and the second proxy cache can receive a write request from a client to modify the cached data and to send the modified cached data to a server.

29. The apparatus of claim 18, wherein each of the first proxy cache and the second proxy cache is configured to verify the cached data.

30. The apparatus of claim 18, wherein the first proxy cache includes a first control manager module, wherein the second proxy cache includes second control manager module, and wherein the first and second control manager modules set a schedule for transmitting the cached data from the first proxy cache to the second proxy cache.

31. The apparatus of claim 18, wherein the first proxy cache includes a first control manager module, wherein the second proxy cache includes second control manager module, and wherein the first and second control manager modules designates the second proxy cache to receive cached data from the first proxy cache and prevent other proxy caches from receiving the cached data.

32. The apparatus of claim 18, wherein the first proxy cache includes a group leader module, wherein the second proxy cache includes group member module, and wherein the group leader module coordinates with the group member module so that the cached data is sent from the first proxy cache to the second proxy cache and so that other proxy caches are prevented from receiving the cached data.

33. The apparatus of claim 18, wherein the first proxy cache includes a group member module, wherein the second proxy cache includes second group member module, and wherein the first and second group member modules configure the first proxy cache and the first proxy cache as belonging to the cluster configuration.

34. The apparatus of claim 18, further comprising:

a timeout header in the cached data, where the timeout header sets a timeout time period when the cached data is eligible for flushing from the second proxy cache.

35. The apparatus of claim 18, further comprising:

a minimum age header in the cached data, where the minimum age header sets an aged time period when the cached data is eligible to be served by the second proxy cache to a requesting client.