SYNCHRONIZATION OF SEQUENTIAL ACCESS STORAGE COMPONENTS WITH BACKUP CATALOG

• US 20110295797A1
• Filed: 05/26/2010
• Published: 12/01/2011
• Est. Priority Date: 05/26/2010
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: PAZ, Gil E., LAZAR, Aharon, MAOZ, Itay, BUDILOVSKY, Evgeny, AKIRAV, Shay H., DROBCHENKO, Elena, LENEMAN, Ofer
• Granted Patent: US 8,266,102 B2
• Time in Patent Office: Days
• US Class Current: 707/613
• CPC Class Codes: G06F 11/1458 Management of the backup or restore process
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence
• CPC Class Codes: G06F 16/273 Asynchronous replication or reconciliation
• CPC Class Codes: G06F 2201/82 Solving problems relating to consistency ensuring consistency in mirrored systems G06F11/2064

Abstract

Various embodiments for synchronization of source and replicated instances of sequential access storage components are provided. Subsequent to a storage operation performed on the source instance by a source component, a synchronization message is sent to a replicated component for the replicated instance. The synchronization message is stored locally in a persistent storage location associated with the source component along with an indicator representative of a time the storage operation was performed. Pursuant to receipt of the synchronization message by the replicated component, the replicated component is updated to a dirty state to indicate a lack of full synchronization between the source and replicated instances. Receipt of the synchronization message is acknowledged by the replicated component by sending a dirty state acknowledgement. If, during a subsequent recovery process, the dirty state is not yet cleared, the replicated component is deemed ineligible for participation in a full restoration operation.

Claims

1. A method for synchronization of source and replicated instances of sequential access storage components with a backup catalog in a computing environment by a processor device, comprising:

subsequent to a storage operation performed on the source instance by a source component, sending a synchronization message to a replicated component for the replicated instance, wherein the synchronization message is stored locally in a persistent storage location associated with the source component along with an indicator representative of a time the storage operation was performed;

pursuant to receipt of the synchronization message by the replicated component, updating the replicated component to a dirty state to indicate a lack of full synchronization between the source and replicated instances; and

acknowledging receipt of the synchronization message by the replicated component to the source component by sending a dirty state acknowledgement;

wherein if, during a subsequent recovery process, the dirty state is not yet cleared, the replicated component is deemed ineligible for participation in a full restoration operation.

2. The method of claim 1, further including creating the synchronization message on the source component.

3. The method of claim 1, further including, if the replicated component has previously sent the dirty state acknowledgment, withholding sending an additional synchronization message.

4. The method of claim 1, further including, subsequent to a completion of a replication operation, clearing the dirty state of the replicated component.

5. The method of claim 1, further including, subsequent to receipt of the synchronization message, storing the synchronization message in a persistent storage location associated with the replicated component.

6. The method of claim 1, further including querying the replicated component for a status of the dirty state using a request handler according to a predefined schedule.

7. The method of claim 6, further including, if at least one of querying the replicated component for the status of the dirty state and updating the replicated component to the dirty state fails, maintaining the at least one of the query and the update for subsequent retry by the source component.

8. The method of claim 7, further including retrying the one of the query and the update according to a user-defined timeframe, wherein:

if the timeframe expires, the one of the query and the update is discarded and an alert is sent to the user, and

if retrying the one of the query and the update is successful, the one of the query and the update is deleted from the source component.

9. A system for synchronization of source and replicated instances of sequential access storage components with a backup catalog in a computing environment, comprising:

at least one processor device operable in the computing environment, the at least one processor in communication with a source component and a replicated component, wherein the at least one processor device is adapted for;

subsequent to a storage operation performed on the source instance by the source component, sending a synchronization message to the replicated component for the replicated instance, wherein the synchronization message is stored locally in a persistent storage location associated with the source component along with an indicator representative of a time the storage operation was performed,

pursuant to receipt of the synchronization message by the replicated component, updating the replicated component to a dirty state to indicate a lack of full synchronization between the source and replicated instances, and

acknowledging receipt of the synchronization message by the replicated component to the source component by sending a dirty state acknowledgement;

wherein if, during a subsequent recovery process, the dirty state is not yet cleared, the replicated component is deemed ineligible for participation in a full restoration operation.

10. The system of claim 9, wherein the at least one processor device is further adapted for creating the synchronization message on the source component.

11. The system of claim 9, wherein the at least one processor device is further adapted for, if the replicated component has previously sent the dirty state acknowledgment, withholding sending an additional synchronization message.

12. The system of claim 9, wherein the at least one processor device is further adapted for, subsequent to a completion of a replication operation, clearing the dirty state of the replicated component.

13. The system of claim 9, wherein the at least one processor device is further adapted for, subsequent to receipt of the synchronization message, storing the synchronization message in a persistent storage location associated with the replicated component.

14. The system of claim 9, wherein the at least one processor device is further adapted for querying the replicated component for a status of the dirty state using a request handler according to a predefined schedule.

15. The system of claim 14, wherein the at least one processor device is further adapted for, if at least one of querying the replicated component for the status of the dirty state and updating the replicated component to the dirty state fails, maintaining the at least one of the query and the update for subsequent retry by the source component.

16. The system of claim 15, wherein the at least one processor device is further adapted for retrying the one of the query and the update according to a user-defined timeframe, wherein:

if the timeframe expires, the one of the query and the update is discarded and an alert is sent to the user, and

if retrying the one of the query and the update is successful, the one of the query and the update is deleted from the source component.

17. A computer program product for synchronization of source and replicated instances of sequential access storage components with a backup catalog in a computing environment by a processor device, the computer program product comprising a computer-readable storage medium having computer-readable program code portions stored therein, the computer-readable program code portions comprising:

a first executable portion for, subsequent to a storage operation performed on the source instance by a source component, sending a synchronization message to a replicated component for the replicated instance, wherein the synchronization message is stored locally in a persistent storage location associated with the source component along with an indicator representative of a time the storage operation was performed;

a second executable portion for, pursuant to receipt of the synchronization message by the replicated component, updating the replicated component to a dirty state to indicate a lack of full synchronization between the source and replicated instances; and

a third executable portion for acknowledging receipt of the synchronization message by the replicated component to the source component by sending a dirty state acknowledgement;

wherein if, during a subsequent recovery process, the dirty state is not yet cleared, the replicated component is deemed ineligible for participation in a full restoration operation.

18. The computer program product of claim 17, further including a fourth executable portion for creating the synchronization message on the source component.

19. The computer program product of claim 17, further including a fourth executable portion for, if the replicated component has previously sent the dirty state acknowledgment, withholding sending an additional synchronization message.

20. The computer program product of claim 17, further including a fourth executable portion for, subsequent to a completion of a replication operation, clearing the dirty state of the replicated component.

21. The computer program product of claim 17, further including a fourth executable portion for, subsequent to receipt of the synchronization message, storing the synchronization message in a persistent storage location associated with the replicated component.

22. The computer program product of claim 17, further including a fourth executable portion for querying the replicated component for a status of the dirty state using a request handler according to a predefined schedule.

23. The computer program product of claim 22, further including a fifth executable portion for, if at least one of querying the replicated component for the status of the dirty state and updating the replicated component to the dirty state fails, maintaining the at least one of the query and the update for subsequent retry by the source component.

24. The computer program product of claim 23, further including a sixth executable portion for retrying the one of the query and the update according to a user-defined timeframe, wherein:

if the timeframe expires, the one of the query and the update is discarded and an alert is sent to the user, and

if retrying the one of the query and the update is successful, the one of the query and the update is deleted from the source component.