System and method for enabling failover for an application server cluster

• US 20030177411A1
• Filed: 03/12/2002
• Published: 09/18/2003
• Est. Priority Date: 03/12/2002
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Tonse, Sudhir, Dinker, Darpan, Gopinath, Pramod, Nadipalli, Suveen R.
• Granted Patent: US 6,944,788 B2
• Time in Patent Office: Days
• US Class Current: 714/13
• CPC Class Codes: G06F 11/2028 eliminating a faulty processor or activating a spare
• CPC Class Codes: G06F 11/2041 with more than one idle spare processing component

Abstract

A system and method for enabling failover in an application server cluster. A “primary” application server computer in the cluster may provide a service or data necessary for other application server computers in the cluster to operate. In addition to the primary application server computer, one or more of the other application server computers may be designated as “backup” application server computers. Each backup application server may backup the processing information managed by the primary application server. When the primary application server itself becomes unavailable (e.g., due to a failure of the computer system or network), one or more of the backup application servers may be promoted to the role of primary application server.

Claims

1. A backup application server computer for use with an application server cluster, wherein the cluster includes a first primary application server computer, wherein the backup application server computer comprises:

a processor; and

a memory storing program instructions;

wherein the processor is operable to execute the program instructions to;

determine that a cluster failure occurred; and

promote the backup application server computer to a primary application server role in response to the cluster failure, wherein said promoting enables the backup application server computer to act as a primary application server computer within the cluster.

2. The backup application server computer of claim 1,

wherein said enabling the backup application server computer to act as a primary application server computer within the cluster comprises enabling the backup application server computer to provide information needed by other application server computers in the cluster to process requests.

3. The backup application server computer of claim 1,

wherein the cluster failure comprises a failure that prevents a primary application server computer in the cluster from acting as a primary application server for one or more application server computers within the cluster;

wherein said promoting the backup application server computer to a primary application server role enables the backup application server computer to act as a primary application server computer for the one or more application server computers.

4. The backup application server computer of claim 1,

wherein the cluster failure comprises one of:

a network failure; and

a computer hardware failure.

5. A backup application server computer for use with an application server cluster, wherein the backup application server computer comprises:

a processor; and

a memory storing program instructions;

wherein the processor is operable to execute the program instructions to;

determine that a failure occurred in the cluster which results in the cluster being divided into a first sub-cluster and a second sub-cluster, wherein application server computers in the first sub-cluster are unreachable from application server computers in the second sub-cluster, wherein the first sub-cluster includes a first primary application server computer, and wherein the second sub-cluster includes the backup application server computer; and

promote the backup application server computer to a primary application server role in response to said determining the network failure, wherein said promoting enables the backup application server computer to act as a primary application server computer within the second sub-cluster.

6. The backup application server computer of claim 5,

wherein the processor is further operable to execute the program instructions to store backup data for the primary application server computer before the failure occurs in the cluster;

wherein said promoting enables the backup application server computer to provide the stored backup data to application server computers in the second sub-cluster.

7. The backup application server computer of claim 5,

wherein said promoting enables the backup application server computer to receive and store data from application server computers in the second sub-cluster.

8. The backup application server computer of claim 5,

wherein the processor is further operable to execute the program instructions to:

determine that the failure was corrected so that application server computers in the first sub-cluster are reachable from application server computers in the second sub-cluster; and

return the backup application server computer to a backup application server role in response to said determining that the failure was corrected, wherein said returning enables the backup application server computer to store backup data for the primary application server computer.

9. The backup application server computer of claim 5,

wherein said determine that a failure occurred in the cluster comprises determining that a network failure occurred in the cluster, wherein the network failure results in the cluster being divided into the first sub-cluster and the second sub-cluster.

10. The backup application server computer of claim 9,

wherein the application server cluster comprises a first plurality of application server computers connected to a first network and a second plurality of application server computers connected to a second network;

wherein said determining that a network failure occurred in the cluster comprises determining that a failure occurred between the first network and the second network;

wherein the first sub-cluster comprises the first plurality of application server computers connected to the first network; and

wherein the second sub-cluster comprises the second plurality of application server computers connected to the second network.

11. A failover method for an application server cluster, the method comprising:

a first application server computer receiving a first client request, wherein the first application server computer is a computer from a cluster of application server computers;

the first application server computer requesting processing information necessary for processing the first client request from a primary application server computer, wherein a backup application server computer is operable to backup the processing information for the primary application server computer;

the first application server computer receiving an indication that the primary application server computer is unreachable;

the first application server computer receiving a second client request; and

the first application server computer requesting processing information necessary for processing the second client request from the backup application server computer.

12. The method of claim 11, further comprising:

promoting the backup application server computer to a primary application server role in response to determining that the primary application server computer is unreachable from one or more application server computers in the cluster;

wherein said promoting the backup application server computer to a primary application server role enables the backup application server computer to provide processing information in response to requests from application server computers in the cluster.

13. A failover method for an application server cluster, the method comprising:

a plurality of application server computers in the cluster receiving a first plurality of client requests;

the plurality of application server computers requesting information for processing the first plurality of client requests from a first application server computer in the cluster, wherein the first application server computer is configured to return the requested information;

configuring a second application server computer in the cluster to return information requested for processing client requests, in response to determining that the first application server computer has become unreachable from a subset of application server computers in the cluster;

the application server computers in the subset receiving a second plurality of client requests; and

the application server computers in the subset requesting information for processing the second plurality of client requests from the second application server computer.

14. An application server cluster comprising:

a primary application server computer;

a backup application server computer;

one or more additional application server computers;

wherein the primary application server computer is operable to provide processing information to the one or more additional application server computers in response to requests from the one or more additional application server computers;

wherein the backup application server computer is operable to backup processing information for the primary application server computer; and

wherein the backup application server computer is operable to promote itself to a primary application server role in response to determining a cluster error, wherein said promoting enables the backup application server computer to provide processing information to the one or more additional application server computers in response to requests from the one or more additional application server computers.

15. A carrier medium comprising program instructions executable by a backup application server computer to:

store backup information received from a primary application server computer;

determine that a cluster failure occurred; and

promote the backup application server computer to a primary application server role in response to said determining the cluster failure, wherein said promoting enables the backup application server computer to act as a primary application server computer within an application server cluster.

16. The carrier medium of claim 15,

wherein said promoting enables the backup application server computer to provide the stored backup information to application server computers in the cluster.

17. The carrier medium of claim 15,

wherein said promoting enables the backup application server computer to receive and store data from application server computers in the cluster.

18. The carrier medium of claim 15, further comprising program instructions executable by the backup application server computer to:

determine that the cluster failure was corrected; and

return the backup application server computer to a backup application server role i response to said determining that the failure was corrected.