Data migration using multi-storage volume swap

Patent metadata

Field	Value
Publication number	US-9405628-B2
Application number	US-201314034518-A
Country	US
Kind code	B2
Filing date	Sep 23, 2013
Priority date	Sep 23, 2013
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

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.

First claim

What is claimed is:

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 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;
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;
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, the method further comprising:
swapping the replacement source storage units for the original source storage units wherein the swapping includes 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 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.

2. The method of claim 1 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.

3. The method of claim 1 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.

4. 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.

5. The method of claim 1 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.

6. 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 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;
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;
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, the system 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 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 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.

7. The system of claim 6 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.

8. The system of claim 6 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.

9. The system of claim 6 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 o

Assignees

• IBM

Inventors

• Blea Amy N
• Blea David R
• Mcbride Gregory E
• Rooney William J
• Wolfgang John J

Classifications

• G06F11/2082

  Data synchronisation · CPC title

• G06F3/067

  Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS] · CPC title

• G06F3/065

  Replication mechanisms · CPC title

• G06F16/119

  Details of migration of file systems (migration mechanisms in storage systems G06F3/0647) · CPC title

• G06F3/0619 Primary

  in relation to data integrity, e.g. data losses, bit errors · CPC title