Method and apparatus for providing process pair protection for complex applications

A computer program product comprising a computer usable medium having computer readable code embodied therein for providing high availability to a complex application through the use of process-pair protection to allow fast and stateful application failover, the computer program product comprising:

• first computer readable program code devices configured to cause a primary computer system to provide a primary process-pair manager to start and manage a primary instance of a complex application;
• second computer readable program code devices configured to cause a backup computer system to provide a backup process pair manager to startup and manage a backup instance of the complex application, the backup process-pair manager and the backup instance of the complex application configured to replace the primary process-pair manager and the primary instance of the complex application in the event of failure of the primary computer system or failure of the primary instance of the complex application;
• wherein the primary process-pair manager and the backup process-pair manager each include an application state model, and each application state model comprises:
• two or more states, with one state being designated as a current state, with states grouped in main states;
• one or more transitions, each transition interconnecting two states, each transition defining the conditions under which a process-pair manager will change the current state to a state interconnected with the current state;
• and
• one or more actions, each action associated with a respective transition, each action being a sequence of steps executed by a process-pair manager when traversing the transition associated with the action.

A method for providing high availability to complex applications through the use of process-pair protection to allow fast and stateful application failover, the method comprising:

• using a primary process-pair manager to start and manage a primary instance of a complex application on a primary computer system;
• using a backup process-pair manager to start and manage a backup instance of a complex application on a backup computer system, wherein the backup process-pair manager and the backup instance of the complex application are configured to replace the primary process-pair manager and the primary instance of the complex application in the event of failure of the primary computer system or failure of the primary instance of the complex application;
• wherein the primary process-pair manager and the backup process-pair manager each include an application state model, and each application state model comprises:
• two or more states, with one state being designated as a current state, with states grouped in main states;
• one or more transitions, each transition interconnecting two states, each transition defining the conditions under which a process-pair manager will change the current state to a state interconnected with the current state;
• and
• one or more actions, each action associated with a respective transition, each action being a sequence of steps executed by a process-pair manager when traversing the transition associated with the action.