Method and system for automated, no downtime, real-time, continuous data protection

• US 7,096,392 B2
• Filed: 05/07/2004
• Issued: 08/22/2006
• Est. Priority Date: 05/07/2004
• Status: Active Grant

• Current Assignee: Quest Software, Inc.
• Original Assignee: Asempra Technologies, Inc. (Quest Software, Inc.)
• Inventors: Sim-Tang, Siew Yong
• Primary Examiner(s): Baderman, Scott
• Assistant Examiner(s): Bonura, Timothy M.
• Application Number:
  US10/841,398
• Publication Number:
  US 20050262377A1
• Time in Patent Office: 837 Days
• Field of Search: 714/4, 714/18, 714/48, 714/49, 714/43, 709/224
• US Class Current: 714/48
• CPC Class Codes: G06F 11/2069 Management of state, configuration or failover
• CPC Class Codes: G06F 2201/82 Solving problems relating to consistency ensuring consistency in mirrored systems G06F11/2064

Abstract

A data management system or “DMS” provides an automated, continuous, real-time, substantially no downtime data protection service to one or more data sources associated with a set of application host servers. To facilitate the data protection service, a host driver embedded in an application server captures real-time data transactions, preferably in the form of an event journal that is provided to other DMS components. The driver functions to translate traditional file/database/block I/O and the like into a continuous, application-aware, output data stream. The host driver includes an event processor that provides the data protection service, preferably by implementing a finite state machine (FSM). In particular, the data protection is provided to a given data source in the host server by taking advantage of the continuous, real-time data that the host driver is capturing and providing to other DMS components. The state of the most current data in DMS matches the state of the data in the host server; as a consequence, the data protection is provided under the control of the finite state machine as a set of interconnected phases or “states.” The otherwise separate processes (initial data upload, continuous backup, blackout and data resynchronization, and recovery) are simply phases of the overall data protection cycle. As implemented by the finite state machine, this data protection cycle preferably loops around indefinitely until, for example, a user terminates the service. A given data protection phase (a given state) changes only as the state of the data and the environment change (a given incident).

Claims

1. Apparatus comprising a processor and program code to implement a finite state machine with a plurality of states and to effect transitions between the states, the finite state machine providing a data protection service to a data source associated with a host and comprising:

a first state for acting upon an upload event;

a second state for acting upon a backup event, the finite state machine transitioning from the first state to the second state upon the occurrence of a given incident;

a third state for acting upon a resynchronization event, the finite state machine transitioning from the second state to the third state upon the occurrence of a given incident;

a fourth state for acting upon a recovery initiation event, the finite state machine transitioning to the fourth state from either the second state or the third state upon the occurrence of a given incident;

a fifth state for acting upon a recovery event, the finite state machine transitioning from the fourth state to the fifth state upon the occurrence of a given incident;

wherein, upon completion of the recovery event, the finite state machine transitions from the fifth state back to the second state upon the occurrence of a given incident; and

a sixth state for acting upon a blackout event that occurs while the finite state machine is in either the second state or the third state;

wherein the finite state machine transitions from the second state to the sixth state upon occurrence of a given incident, wherein the given incident that causes this transition is a blackout that occurs while the finite state machine is in the second state or the third state.

2. The apparatus as described in claim 1 wherein the finite state machine transitions from the sixth state back to the third state upon the occurrence of a given incident while the finite state machine is in the sixth state.

3. The apparatus as described in claim 2 wherein the given incident that causes the finite state machine to transition from the sixth state back to the third state is a reconnection.

4. The apparatus as described in claim 1 wherein the given incident that causes the finite state machine to transition from the first state to the second state while the finite state machine is in the first state is completion of an upload of a baseline copy of the data source.

5. The apparatus as described in claim 1 wherein the given incident that causes the finite state machine to transition from the second state to the third state while the finite state machine is in the second state is a reboot.

6. The apparatus as described in claim 1 wherein the given incident that causes the finite state machine to transition from the second state to the fourth state while the finite state machine is in the second state is a request to initiate a recovery.

7. The apparatus as described in claim 1 wherein the given incident that causes the finite state machine to transition from the third state to the fourth state while the finite state machine is in the third state is a request to initiate a recovery.

8. The apparatus as described in claim 1 wherein the finite state machine transitions from the third state back to the second state upon the occurrence of a given incident, wherein the given incident that causes this transition is an indication that given data is synchronized.

9. The apparatus as described in claim 1 wherein the given incident that causes the finite state machine to transition from the fourth state to the fifth state while the finite state machine is in the fourth state is an indication that given data recovery is initiated.

10. The apparatus as described in claim 1 wherein the given incident that causes the finite state machine to transition from the fifth state back to the second state while the finite state machine is in the fifth state is an indication that given data recovery is completed.

11. A method of protecting a data source associated with an application, comprising:

generating an application aware, real-time event data stream by capturing data changes associated with one or more events associated with the data source, the data stream comprising, for each event, data identifying the event, given metadata, and the data changes; and

protecting the data source without substantially interrupting the application by continuously transitioning among a set of states.

12. The method as described in claim 11 wherein the set of states comprise:

a first state for acting upon an upload event;

a second state for acting upon a backup event, the first state transitioning to the second state upon the occurrence of a given incident;

a third state for acting upon a resynchronization event, the second state transitioning to the third state upon the occurrence of a given incident; and

a fourth state for acting upon a recovery event, the fourth state being reached by a transition from either a backup event or a resynchronization event;

wherein, upon completion of the recovery event, the fourth state transitions back to the second state.

13. A method of protecting a data source associated with a host, comprising:

generating an application aware, real-time event data stream; and

protecting the data source without interrupting the application, wherein data protection is provided by continuously transitioning among a set of states, comprising;

a first state for acting upon an upload event;

a second state for acting upon a backup event, the first state transitioning to the second state upon the occurrence of a given incident;

a third state for acting upon a resynchronization event, the second state transitioning to the third state upon the occurrence of a given incident;

a fourth state for acting upon a recovery initiation event, the fourth state being reached by a transition from either the second state or the third state upon the occurrence of a given incident;

a fifth state for acting upon a recovery event, the fourth state transitioning to the fifth state upon the occurrence of a given incident;

wherein, upon completion of the recovery event, the fifth state transitions back to the second state upon the occurrence of a given incident; and

a sixth state for acting upon a blackout event that occurs during either the second state or the third state, wherein, upon occurrence of a given incident, the second state or the third state, as the case may be, transitions to the sixth state.

14. A method of protecting a data source associated with an application, comprising:

generating from the data source an application aware, real-time event data stream by capturing data changes associated with one or more events associated with the data source, the data stream comprising, for each event, data identifying the event, given metadata, and the data changes; and

providing the data source initial data upload, continuous backup, data resynchronization and data recovery as phases of an integrated data protection cycle without substantially interrupting the application.

20. The method as described in claim 14 further including the step of transferring the application aware, real-time event data stream to a data store.

21. The method as described in claim 20 wherein the application-aware, real-time event data stream is transferred to the data store over a network for tracking update history.

15. A computer program stored on a computer recordable medium for providing a data protection service to a data source associated with an application, comprising:

program code executable in a processor that generates an application aware, real-time event data stream associated with the data source by capturing data changes associated with one or more events associated with the data source, the data stream comprising, for each event, data identifying the event, given metadata, and the data changes; and

program code executable in a processor to implement a finite state machine, the finite state machine protecting the data source without substantially interrupting the application by continuously transitioning among a set of states, the set of states comprising data upload, data backup, data resynchronization and data recovery.

16. The computer program product as described in claim 15 wherein the states are phases of an integrated data protection cycle for the data source.

17. The computer program product as described in claim 15 wherein the finite state machine has a given entry state.

18. The computer program product as described in claim 17 wherein the given entry state is the data upload state.

19. The computer program product as described in claim 15 wherein the finite state machine has a given entry state, wherein the given entry state is selected from a set of states that include:

data upload, data backup, data resynchronization and data recovery.