International Business Machines Corporation

John Jay Wolfgang

Kenneth Wayne Boyd

Kenneth Fairclough Day, Iii

Philip Matthew Doatmas

Gregory E McBride

David Randall Blea

Kenneth F Day, Iii

Amy N Blea

Philip Matthew Dudas

William J Rooney

Kirby Grant Dahman

William Frank Micka

Aviad Zlotnick

Henry Esmond Butterworth

Todd Benjamin Schlomer

Michael Edward Factor

David Allan Pease

Amiram Hayardeny

Errol Jay Calder

Charles William Lickel

William D Olsen

Vitaly Zautner

Harry M Yudenfriend

Carlos Francisco Fuente

Ying Chen

Mark Edward Dean

Robert Frederic Kern

John Thomas Flynn, Jr

Benjamin J Randall

Steven M Kern

Stephen F Edel

Jeffrey R Placer

Jacob A Stevens

Kenneth Fairclough Day Iii

Phillip Matthew Doatmas

In one embodiment, I/O operations may be swapped from an original storage unit to a replacement storage unit in a manner which can reduce or eliminate delays caused by copying of data from the original storage unit to the replacement storage unit. A point-in-time snap copy relationship between the original storage unit and the replacement storage unit of storage locations is established and I/O operations are swapped from the original storage unit to the replacement storage unit. The I/O operations are resumed, accessing the replacement storage unit instead of the original storage unit in the input/output operations issued by the at least one host. Other aspects are described.

Storage unit replacement using point-in-time snap copy

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.

Data migration using multi-storage volume swap

A method according to one embodiment includes receiving instruction to change from an original target storage subsystem in a disaster recovery configuration-to a new target storage subsystem. Second copy services relationships are created between one or more new target volumes on the new target storage subsystem and one or more source volumes on a source storage subsystem using multi-target functionality. Existing first copy services relationships between the source storage subsystem and the original target storage subsystem are terminated after all of the second copy services relationships are full duplex.

Automated migration to a new copy services target storage system to manage multiple relationships simultaneously while maintaining disaster recovery consistency

A system according to one embodiment, includes one or more source volumes on a source storage subsystem from which data is copied in first copy services relationships, the one or more source volumes being accessible to an application; one or more original target volumes on an original target storage subsystem to which data is copied in the first copy services relationships; logic configured for selecting a new target storage subsystem to replace the original target storage subsystem; logic configured for creating second copy services relationships between one or more new target volumes on the new target storage subsystem and the one or more source volumes on the source storage subsystem using multi-target functionality; and logic configured for terminating the first copy services relationships after all of the second copy services relationships are full duplex.

In one embodiment, a method for switching a storage subsystem in a disaster recovery configuration includes receiving instruction to change from an original target storage subsystem in a disaster recovery configuration including: a source storage subsystem including one or more source volumes from which data is copied in first copy services relationships, the one or more source volumes being accessible to an application, and the original target storage subsystem including one or more original target volumes to which data is copied in the first copy services relationships; selecting a new target storage subsystem to replace the original target storage subsystem, creating second copy services relationships between one or more new target volumes on the new target storage subsystem and the one or more source volumes on the source storage subsystem using multi-target functionality, and terminating the first copy services relationships after all the second copy services relationships are full duplex.

Aspects of the present invention relate to data migration and/or disaster recovery. One embodiment enables merging of bitmaps to allow for automation of the process of switching to a different target volume on the same storage subsystem without major interruption of data recovery capability and limited interruption of host I/O to the source volumes during the migration. In one approach, the migration of data onto a new target volume within the same storage subsystem as the original target volume is automated, without requiring the user to manually create or remove any new copy relationships.

Automated migration to a new target volume via merged bitmaps to maintain consistency

In one embodiment, a computer program product includes a computer readable storage medium having computer readable program code embodied therewith, configured for: validating a replication of copy services between a first storage system and a second storage system, removing a plurality of existing copy relationships between the first storage system and a failed storage system, creating a plurality of copy relationships between the first storage system and the second storage system, and synchronizing a plurality of data between the first storage system and the second storage system. In more embodiments, a system includes logic for performing the above functionality, and a method includes steps for performing the above functionality.

Acquiring a storage system into copy services management software

An apparatus, system, and method are disclosed for determining prefetch data. A start module communicates a start of a target software process to a storage device. A learning module learns data blocks accessed for the target software process. In one embodiment, a prefetch module prefetches the learned data blocks in response to the start of the target software process. An end module communicates the end of the target software process to the storage device. In one embodiment, the prefetch module terminates prefetching data blocks and the learning module terminates learning the data blocks accessed for the target software process in response to the end module's communication of the end of the target software process.

Monitoring program execution to learn data blocks accessed by software process for facilitating efficient prefetching

A method is disclosed for reliably updating a data group in a read-before-write data replication environment. The method reliably updates the data group by receiving an updated data group sent from a first storage medium to a second storage medium, comparing the updated data group with a previous data group previously existing on the second storage medium and writing the updated data group to the second storage medium. The read-before-write and differencing method disclosed maintain reliability by storing multiple copies of changes made to the second storage medium during and after the write process.

Method for reliably updating a data group in a read-before-write data replication environment using a comparison file

Methods and apparatus are provided for copying data from a primary storage facility to a secondary storage facility which reduce the workload on the storage controller in the primary facility and minimize bandwidth usage. The primary storage facility includes a primary data replication appliance which transfers data to a secondary replication appliance. Updated data from a host is both stored through a storage controller in the primary facility and also received by the primary replication appliance. Logic in the primary replication appliance determines whether the immediately previous version of the data is in a buffer from a previous storage operation. If so, the current (updated) version of the data is compared with the previous version and the difference, such as calculated through a bit-wise exclusive-OR operation, is transferred to the secondary replication appliance. The process is reversed in the secondary replication appliance and the recreated updated version of the data stored in the secondary facility.

Transferring data from a primary data replication appliance in a primary data facility to a secondary data replication appliance in a secondary data facility

An apparatus, system, and method are disclosed for a read-before-write storage controller instruction. A sequencer receives an atomic read-before-write instruction comprising new data, a target address for the new data, and an undo log address. An I/O unit reads old data from the target address, writes the old data and the target address to the undo log address, and writes the new data to the target address as directed by the sequencer.

Apparatus, system, and method for a read-before-write storage controller instruction

Growing community of inventors

Midlothian, VA, United States of America

John Jay Wolfgang