Data migration using multi-storage volume swap

• US 10,146,453 B2
• Filed: 06/29/2016
• Issued: 12/04/2018
• Est. Priority Date: 09/23/2013
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Blea, Amy N., Blea, David R., McBride, Gregory E., Rooney, William J., Wolfgang, John J.
• Primary Examiner(s): NGUYEN, MERILYN P
• Application Number:
  US15/197,612
• Publication Number:
  US 20160313935A1
• Time in Patent Office: 888 Days
• CPC Class Codes: G06F 11/14 Error detection or correction of the data by redundancy in operation G06F11/16 takes precedence
• CPC Class Codes: G06F 11/2069 Management of state, configuration or failover
• CPC Class Codes: G06F 11/2082 Data synchronisation
• CPC Class Codes: G06F 16/119 Details of migration of file systems migration mechanisms in storage systems G06F3/0647
• CPC Class Codes: G06F 16/273 Asynchronous replication or reconciliation
• CPC Class Codes: G06F 3/06 Digital input from, or digital output to, record carriers , e.g. RAID, emulated record carriers or networked record carriers
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

In one embodiment of the present description, data is migrated to a replacement source storage unit of a storage subsystem while being mirrored from the original source storage unit of a storage subsystem to an original target storage unit of a storage subsystem, and the original source storage unit and the replacement storage unit are swapped in a multi-storage volume swap to write updates to the replacement source storage unit instead of the original source storage unit, in input/output operations issued by at least one host. Further, data stored in the replacement source storage unit, is mirrored from the replacement source storage unit to the original target unit. Other aspects are described.

Claims

1. A method, comprising:

writing updates to original source storage units in response to received input/output operations;

mirroring data stored in the original source storage units including the updates, from the original source storage units to original target storage units while updates are actively being written to the original source storage units;

migrating the data stored in the original source storage units including the updates from the original source storage units to associated replacement source storage units while actively mirroring the data stored in the original source storage units including the updates, from the original source storage units to the original target storage units;

quiescing input/output operations to original source storage units when migrating to associated replacement source storage units is complete so that associated replacement source storage units are complete copies of associated original source storage units,

resuming input/output operations and writing updates to the replacement source storage units instead of to the original source storage units, in response to received input/output operations; and

mirroring data stored in the replacement source storage units, from the replacement source storage units to the original target storage units.

2. The method of claim 1 wherein the mirroring data stored in the original source storage units includes mirroring data from the original source storage units to the original target storage units in copy relationships with associated original source storage units.

3. The method of claim 2 further comprising swapping the replacement source storage units for the original source storage units wherein the swapping includes the quiescing input/output operations to the original source storage units, terminating the copy relationships of the target storage units with associated original source storage units, reestablishing the copy relationships as copy relationships of the original target storage units with associated replacement source storage units, and the resuming input/output operations wherein the writing updates to the replacement source storage units instead of the original source storage units is in response to the resumed input/output operations issued by at least one host, and wherein the mirroring data stored in the replacement source storage units includes mirroring data from the replacement source storage units to the original target storage units in the reestablished copy relationships with associated replacement source storage units.

4. The method of claim 2 wherein the migrating includes in response to a command, automatically establishing copy relationships of the replacement source storage units with associated storage units of the original source storage units based upon the copy relationships of the original target storage units with associated original source storage units.

5. The method of claim 3 wherein the terminating the copy relationships of the original target storage units with associated original source storage units and the reestablishing the copy relationships as copy relationships of the original target storage units with associated replacement source storage units, are performed automatically in response to a command.

6. The method of claim 1 further comprising:

maintaining a capability to swap the original source storage units and the original target storage units to write updates to the original target storage units instead of to the original source storage units, in input/output operations issued by at least one host, in the event of a failure at the original source storage units while actively migrating the data stored in the original source storage units from the original source storage units to the replacement source storage units.

7. The method of claim 3 further comprising determining when the migrating of the data stored in the original source storage units including the updates from the original source storage units to the replacement source storage units is at least one of complete and predominantly complete, and wherein said swapping is initiated in response to a determination that the migrating of the data stored in the original source storage units including the updates from the original source storage units to the replacement source storage units is at least one of complete and predominantly complete.

8. A system, comprising:

at least one storage subsystem including a plurality of original source storage units, a plurality of original target storage units, a plurality of replacement source storage units and at least one storage controller adapted to access and control storage units of the at least one storage subsystem; and

at least one computer readable storage medium having computer readable program code embodied therein that is enabled to cause operations to be performed, the operations comprising;

writing updates to original source storage units in response to received input/output operations;

mirroring data stored in the original source storage units including the updates, from the original source storage units to original target storage units while updates are actively being written to the original source storage units;

migrating the data stored in the original source storage units including the updates from the original source storage units to associated replacement source storage units while actively mirroring the data stored in the original source storage units including the updates, from the original source storage units to the original target storage units;

quiescing input/output operations to original source storage units when migrating to associated replacement source storage units is complete so that associated replacement source storage units are complete copies of associated original source storage units,

resuming input/output operations and writing updates to the replacement source storage units instead of to the original source storage units, in response to received input/output operations; and

mirroring data stored in the replacement source storage units, from the replacement source storage units to the original target storage units.

9. The system of claim 8 wherein the mirroring data stored in the original source storage units includes mirroring data from the original source storage units to the original target storage units in copy relationships with associated original source storage units.

10. The system of claim 9 further comprising at least one host wherein the operations further comprise swapping the replacement source storage units for the original source storage units wherein the swapping includes the quiescing input/output operations to the original source storage units, terminating the copy relationships of the target storage units with associated original source storage units, reestablishing the copy relationships as copy relationships of the original target storage units with associated replacement source storage units, and the resuming input/output operations wherein the writing updates to the replacement source storage units instead of the original source storage units is in response to the resumed input/output operations issued by at least one host, and wherein the mirroring data stored in the replacement source storage units includes mirroring data from the replacement source storage units to the original target storage units in the reestablished copy relationships with associated replacement source storage units.

11. The system of claim 9 wherein the migrating includes in response to a command, automatically establishing copy relationships of the replacement source storage units with associated storage units of the original source storage units based upon the copy relationships of the original target storage units with associated original source storage units.

12. The system of claim 10 wherein the terminating the copy relationships of the original target storage units with associated original source storage units and the reestablishing the copy relationships as copy relationships of the original target storage units with associated replacement source storage units, are performed automatically in response to a command.

13. The system of claim 10 wherein the operations further comprise:

maintaining a capability to swap the original source storage units and the original target storage units to write updates to the original target storage units instead of to the original source storage units, in input/output operations issued by at least one host, in the event of a failure at the original source storage units while actively migrating the data stored in the original source storage units from the original source storage units to the replacement source storage units.

14. The system of claim 10 wherein the operations further comprise determining when the migrating of the data stored in the original source storage units including the updates from the original source storage units to the replacement source storage units is at least one of complete and predominantly complete, and wherein said swapping is initiated in response to a determination that the migrating of the data stored in the original source storage units including the updates from the original source storage units to the replacement source storage units is at least one of complete and predominantly complete.

15. A computer program product for managing data storage operations in connection with at least one storage subsystem including a plurality of original source storage units, a plurality of original target storage units, a plurality of replacement source storage units, and at least one storage controller adapted to access and control storage units of the at least one storage subsystems, the computer program product comprising at least one computer readable storage medium having computer readable program code embodied therein that is enabled to cause operations to be performed, the operations comprising:

writing updates to original source storage units in response to received input/output operations;

mirroring the data stored in the original source storage units including the updates, from the original source storage units to original target storage units while updates are actively being written to the original source storage units;

migrating the data stored in the original source storage units including the updates from the original source storage units to associated replacement source storage units while actively mirroring the data stored in the original source storage units including the updates, from the original source storage units to the original target storage units;

quiescing input/output operations to original source storage units when migrating to associated replacement source storage units is complete so that associated replacement source storage units are complete copies of associated original source storage units,

resuming input/output operations and writing updates to the replacement source storage units instead of to the original source storage units, in response to received input/output operations; and

mirroring data stored in the replacement source storage units, from the replacement source storage units to the original target storage units.

16. The computer program product of claim 15 wherein the mirroring data stored in the original source storage units includes mirroring data from the original source storage units to the original target storage units in copy relationships with associated original source storage units.

17. The computer program product of claim 16 also for managing data storage operations in connection with at least one host, wherein the operations further comprise swapping the replacement source storage units for the original source storage units wherein the swapping includes the quiescing input/output operations to the original source storage units, terminating the copy relationships of the target storage units with associated original source storage units, reestablishing the copy relationships as copy relationships of the original target storage units with associated replacement source storage units, and the resuming input/output operations wherein the writing updates to the replacement source storage units instead of the original source storage units is in response to the resumed input/output operations issued by at least one host, and wherein the mirroring data stored in the replacement source storage units includes mirroring data from the replacement source storage units to the original target storage units in the reestablished copy relationships with associated replacement source storage units.

18. The computer program product of claim 16 wherein the migrating includes in response to a command, automatically establishing copy relationships of the replacement source storage units with associated storage units of the original source storage units based upon the copy relationships of the original target storage units with associated original source storage units.

19. The computer program product of claim 17 wherein the terminating the copy relationships of the original target storage units with associated original source storage units and the reestablishing the copy relationships as copy relationships of the original target storage units with associated replacement source storage units, are performed automatically in response to a command.

20. The computer program product of claim 17 wherein the operations further comprise:

maintaining a capability to swap the original source storage units and the original target storage units to write updates to the original target storage units instead of to the original source storage units, in input/output operations issued by at least one host, in the event of a failure at the original source storage units while actively migrating the data stored in the original source storage units from the original source storage units to the replacement source storage units.

21. The computer program product of claim 17 wherein the operations further comprise determining when the migrating of the data stored in the original source storage units including the updates from the original source storage units to the replacement source storage units is at least one of complete and predominantly complete, and wherein said swapping is initiated in response to a determination that the migrating of the data stored in the original source storage units including the updates from the original source storage units to the replacement source storage units is at least one of complete and predominantly complete.