Point-in-time copies in a cascade using maps and fdisks
AssigneeInternational Business Machines Corporation
InventorsJohn P. Agombar, Christopher B. Beeken, Carlos F. Fuente, William J. Scales
Life of this patent
Estimating the term…
Abstract
A technique for handling a FlashCopy® process includes receiving a FlashCopy® instruction for a source disk, performing a FlashCopy® point in time copy of the source disk on to a target disk, creating a map specifying the FlashCopy® point in time copy from the source disk to the target disk, creating a primary fdisk for the source disk, if one does not already exist, and creating a primary fdisk for the target disk, if one does not already exist, or, if one does already exist, converting the existing primary fdisk for the target disk into a secondary fdisk, and creating a new primary fdisk for the target disk.
Claims7
A method of handling a copy process comprising:
- for a point in time copy from a source disk to a target disk that are part of a cascade of disks, wherein the cascade represents a series of point in time copies between the disks, creating a map specifying the point in time copy from the source disk to the target disk;
- in response to determining that a primary fdisk does not exist for the source disk, creating the primary fdisk for the source disk, wherein the primary fdisk for the source disk comprises an object that links the source disk to maps upstream and downstream within the cascade;
- in response to determining that a primary fdisk does not exist for the target disk, creating the primary fdisk for the target disk, wherein the primary fdisk for the target disk comprises an object that links the target disk to maps upstream and downstream within the cascade;
- and
- in response to determining that the primary fdisk for the target disk does exist,
- converting the existing primary fdisk for the target disk into a secondary fdisk;
- and
- creating a new primary fdisk for the target disk.
Dependencies are inferred from the claim text.