Bitmap selection for remote copying of updates

摘要

In one embodiment of the present description, a copy relationship is established between a storage location at a first site and a storage location at a second site in a data storage system, wherein a dynamically assignable bitmap preset to one of a plurality of different predetermined bit patterns is selected as a function of both the availability of the selected bitmap and the type of predetermined bit pattern identified for the selected bitmap. The selected bitmap may be assigned as an out-of-sync bitmap wherein updates to the storage location at one site, which are to be copied to the storage location at the other site, are indicated in the selected bitmap, and data writes being written to the storage location at the one site, are copied to the storage location at the other site, using the selected bitmap as an out-of-sync bitmap. Other aspects are described.

主权项

1. An article of manufacture including a computer readable storage medium having code for managing the copying of data between a first storage system including a first storage controller, and a second storage system including a second storage controller, wherein the code is enabled to cause operations to be performed, the operations comprising:
establishing a copy relationship between a storage location at a first site and a storage location at a second site in a data storage system, wherein said establishing includes: selecting a dynamically assignable bitmap preset to one of a plurality of different predetermined bit patterns as a function of both the availability of the selected bitmap and the type of predetermined bit pattern identified for the selected bitmap; assigning the selected bitmap as an out-of-sync bitmap wherein updates to the storage location at the second site, which are to be copied to the storage location at the first site, are indicated in the selected bitmap; copying data writes being written to the storage location at the second site, to the storage location at the second site, using the selected bitmap as an out-of-sync bitmap; and receiving an establish command wherein said copy relationship establishing is in response to said establish command; wherein the bitmap selecting includes:
determining if a failover parameter has been set in the received establish command;selecting a dynamically assignable bitmap preset to a first predetermined bit pattern if it is determined that a failover parameter has been set in the received establish command;determining if a copy all parameter has been set in the received establish command; andselecting a dynamically assignable bitmap preset to a second predetermined bit pattern different from the first predetermined bit pattern, if it is determined that a copy all parameter has been set in the received establish command.