Method, system and program products for automatically connecting a client to a server of a replicated group of servers

• US 7,133,891 B1
• Filed: 05/31/2000
• Issued: 11/07/2006
• Est. Priority Date: 05/31/2000
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Uceda-Sosa, Rosario A., Novaes, Marcos N., Marthi, Kailash N., Champagne, Steven R., Laib, Gregory D.
• Primary Examiner(s): Najjar, Saleh
• Assistant Examiner(s): WON, MICHAEL YOUNG
• Application Number:
  US09/583,694
• Time in Patent Office: 2,351 Days
• Field of Search: 709/200, 709/201, 709/220, 709/221, 709/227, 709/209, 709/203, 714/4
• US Class Current: 709/203
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/1034 Reaction to server failures by a load balancer
• CPC Class Codes: H04L 67/289 Intermediate processing functionally located close to the data consumer application, e.g. in same machine, in same home or in same sub-network
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/563 Data redirection of data network streams

Abstract

A client application sends a request to a given server of a replicated group of servers, and expects a response to the request. If the client does not receive a response to the request, or if the server is otherwise unavailable, the client is automatically reconnected to another server of the replicated group. The servers of the replicated group do not, however, have to have any knowledge of the communication session of the client.

Claims

1. A method of managing connections between clients and servers of a distributed computing environment, said method comprising:

determining, by a client of said distributed computing environment, that a server coupled to said client, via a communications protocol that lacks individualized timeouts for individual components of said distributed computing environment, is unavailable to process requests for said client, wherein said server is a member of a group of a plurality of replicated servers; and

directly connecting, by said client, said client to another replicated server of said group, wherein servers of said group lack knowledge of application-level information of a communication session of said client.

2. The method of claim 1, wherein the determining is performed by a client request broker.

3. The method of claim 1, wherein the determining comprises causing at least one ping message to be sent to the server.

4. The method of claim 3, wherein the causing comprises causing a plurality of ping messages to be sent to the server.

5. The method of claim 4, wherein the causing comprises causing the plurality of ping messages to be sent to the server in accordance with a dynamic ping interval.

6. The method of claim 5, wherein the dynamic ping interval is based on a workload level of the server.

7. The method of claim 4, wherein the determining comprises determining that a predetermined number of the plurality of ping messages have failed.

8. The method of claim 1, wherein the connecting comprises first determining that the another replicated server is available.

9. The method of claim 8, further comprising:

routing non-idempotent client requests from the another replicated server to the server if the server is still part of the group; and

sending results of processing the non-idempotent client requests to the another replicated server.

10. A system of managing connections between clients and servers of a distributed computing environment, said system comprising:

means for determining, by a client of said distributed computing environment, that a server coupled to said client, via a communications protocol that lacks individualized timeouts for individual components of said distributed computing environment, is unavailable to process requests for said client, wherein said server is a member of a group of a plurality of replicated servers; and

means for directly connecting, by said client, said client to another replicated server of said group, wherein servers of said group lack knowledge of application-level information of a communication session of said client.

11. The system of claim 10, wherein the means for determining comprises means for determining by a client request broker.

12. The system of claim 10, wherein the means for determining comprises means for causing at least one ping message to be sent to the server.

13. The system of claim 12, wherein the means for causing comprises means for causing a plurality of ping messages to be sent to the server.

14. The system of claim 13, wherein the means for causing comprises means for causing the plurality of ping messages to be sent to the server in accordance with a dynamic ping interval.

15. The system of claim 14, wherein the dynamic ping interval is based on a workload level of the server.

16. The system of claim 13, wherein the means for determining comprises means for determining that a predetermined number of the plurality of ping messages have failed.

17. The system of claim 10, wherein the means for connecting comprises means for first determining that the another replicated server is available.

18. The system of claim 17, further comprising:

means for routing non-idempotent client requests from the another replicated server to the server if the server is still part of the group; and

means for sending results of processing the non-idempotent client requests to the another replicated server.

19. At least one program storage device readable by a machine, tangibly embodying at least one program of instructions executable by the machine to perform a method of managing connections between clients and servers of a distributed computing environment, said method comprising:

determining, by a client of said distributed computing environment, that a server coupled to said client, via a communications protocol that lacks individualized timeouts for individual components of said distributed computing environment, is unavailable to process requests for said client, wherein said server is a member of a group of a plurality of replicated servers; and

directly connecting, by said client, said client to another replicated server of said group, wherein servers of said group lack knowledge of application-level information of a communication session of said client.

20. The at least one program storage device of claim 19, wherein the determining is performed by a client request broker.

21. The at least one program storage device of claim 19, wherein the determining comprises causing at least one ping message to be sent to the server.

22. The at least one program storage device of claim 21, wherein the causing comprises causing a plurality of ping messages to be sent to the server.

23. The at least one program storage device of claim 22, wherein the causing comprises causing the plurality of ping messages to be sent to the server in accordance with a dynamic ping interval.

24. The at least one program storage device of claim 23, wherein the dynamic ping interval is based on a workload level of the server.

25. The at least one program storage device of claim 22, wherein the determining comprises determining that a predetermined number of the plurality of ping messages have failed.

26. The at least one program storage device of claim 19, wherein the connecting comprises first determining that the another replicated server is available.

27. The at least one program storage device of claim 26, further comprising:

routing non-idempotent client requests from the another replicated server to the server if the server is still part of the group; and

sending results of processing the non-idempotent client requests to the another replicated server.