Method and system for providing high availability to computer applications

• US 7,783,914 B1
• Filed: 12/15/2008
• Issued: 08/24/2010
• Est. Priority Date: 08/26/2004
• Status: Active Grant

• Current Assignee: Red Hat, Inc. (International Business Machines Corporation)
• Original Assignee: Open Invention Network LLC
• Inventors: Havemose, Allan
• Primary Examiner(s): Baderman; Scott T
• Assistant Examiner(s): Leibovich; Yair
• Application Number:
  US12/334,649
• Time in Patent Office: 617 Days
• Field of Search: 714/10, 714/6, 714/4
• US Class Current: 714/4.11
• CPC Class Codes: G06F 11/0709 in a distributed system consisting of a plurality of standalone computer nodes, e.g. clusters, client-server systems
• CPC Class Codes: G06F 11/1402 Saving, restoring, recovering or retrying
• CPC Class Codes: G06F 11/141 for bus or memory accesses
• CPC Class Codes: G06F 11/1438 Restarting or rejuvenating
• CPC Class Codes: G06F 11/1482 by means of middleware or OS functionality
• CPC Class Codes: G06F 11/20 using active fault-masking, e.g. by switching out faulty elements or by switching in spare elements
• CPC Class Codes: G06F 11/2002 where interconnections or communication control functionality are redundant flexible arrangements for bus networks involving redundancy H04L12/40176
• CPC Class Codes: G06F 11/2023 Failover techniques
• CPC Class Codes: G06F 11/2028 eliminating a faulty processor or activating a spare
• CPC Class Codes: G06F 11/203 using migration
• CPC Class Codes: G06F 11/2046 where the redundant components share persistent storage G06F11/2043 takes precedence
• CPC Class Codes: G06F 11/30 Monitoring
• CPC Class Codes: H04L 61/5007 Internet protocol [IP] addresses

Abstract

A system and method for performing loss-less migration of an application program from a primary node to a backup node. All application state for the application program on the primary node are captured and transmitted to the backup node. TCP/IP connection state is restored for all connections; and internals of the application program are remapped to an operating system and to system libraries on the backup node.

Claims

1. A method for performing loss-less migration of an application program from a primary node to a backup node, the method comprising:

capturing all application state for the application program on the primary node;

transmitting the application state to the backup node;

restoring TCP/IP connection state for all connections; and

remapping internals of the application program to an operating system and system libraries on the backup node, wherein the application program is selected from the group consisting of an operating system service, a device driver, and a kernel module.

2. The method according to claim 1, further comprising:

recreating an application image from the application state; and

remapping application resources against underlying hardware.

3. The method according to claim 1, wherein the application program is a user-space application.

4. The method according to claim 1, wherein the application program is virtual machine software.

5. The method according to claim 1, further comprising:

disconnecting clients during the loss-less migration; and

accepting client-reconnects on the backup node after completion of the loss-less migration.

6. A computer readable storage medium including a computer program having instructions for performing loss-less migration of an application program from a primary node to a backup node, wherein the computer program performs steps comprising:

capturing all application state for the application program on the primary node;

transmitting the application state to the backup node;

restoring TCP/IP connection state for all connections; and

remapping internals of the application program to an operating system and system libraries on the backup node, wherein the application program is selected from the group consisting of an operating system service, a device driver, and a kernel module.

7. The computer readable storage medium according to claim 6, wherein the computer program further performs steps of:

recreating an application image from the application state; and

remapping application resources against underlying hardware.

8. The computer readable storage medium according to claim 6, wherein the application program is a user-space application.

9. The computer readable storage medium according to claim 7, wherein the application program is virtual machine software.

10. The computer readable storage medium according to claim 6, wherein the computer program further performs steps of:

disconnecting clients during the loss-less migration; and

accepting client-reconnects on the backup node after completion of the loss-less migration.

11. A communications network for performing loss-less migration of an application program from a primary node to a backup node, the communications network comprising:

a first server structured to run the application program;

a second server in communication with the first server, and structured to operate as a back-up server for the first server; and

at least one computer readable medium associated with the first server and the second server, the at least one computer readable medium including a computer program having instructions for;

capturing all application state for the application program on the primary node;

transmitting the application state to the backup node;

restoring TCP/IP connection state for all connections; and

remapping internals of the application program to an operating system and system libraries on the backup node, wherein the application program is selected from the group consisting of an operating system service, a device driver, and a kernel module.

12. The communications network according to claim 11, wherein the computer program has further instructions for recreating an application image from the application state.

13. The communications network according to claim 11, wherein the computer program has further instructions for remapping application resources against underlying hardware.

14. The communications network according to claim 11, wherein the application program is a user-space application.

15. The communications network according to claim 11, wherein the application program is virtual machine software.

16. The communications network according to claim 11, wherein the computer program has further instructions for disconnecting clients during the loss-less migration.

17. The communications network according to claim 11, wherein the computer program has further instructions for accepting client-reconnects on the backup node after completion of the loss-less migration.