The following table compares how relationships are withdrawn for Hitachi Compatible FlashCopy® and IBM® FlashCopy®.
|
Feature |
IBM® FlashCopy® |
Hitachi Compatible FlashCopy® |
|---|---|---|
|
Withdraw command with a specified extent area. See the following figure. |
The command deletes the relationships within the specified extent area. When the specified extent area is included only in a part of the central existing relationship area, only the existing relationships of the area will be divided. |
When a part of the existing relationship area is included in the extent area specified by the withdraw command, the existing relationship is not released, except in some exceptional cases. If you specify DDSW(YES) or if the range specified with SDEVN contains at least part of the relationship source, the relationship is released after a background copy is executed. |
|
REMOVEFCPY (ICKDSF CONTROL command) |
The command will finish normally. Relationships will not be deleted. |
Not supported. The command will finish abnormally. Relationships will not be deleted. |
|
Establishing a dataset relationship using DFSMSdss, and specifying the source or target volume of a volume relationship as the copy target |
Part of the volume relationship is withdrawn. |
|
Note: Creating a relationship can fail if any of the following events occur:
- A scratch operation
- Deletion of datasets
- Volume initialization
To avoid this problem, use the FCWITHDR command to withdraw the relationship, or wait until the background copy operation is completed and the relationship is withdrawn. For information about scratch operations, see the IBM® Device Support Facilities (ICKDSF) User's Guide and Reference.