HP XP P9500 Storage - Manual (Page 10)

Copying by volume
If you do not specify an extent when you establish a relationship, the entire volume is copied. This
is called volume copying. To perform volume copying, the capacity of the copy source volume
must be equal to or larger than the capacity of the copy target volume. Only a complete volume
can be copied using Compatible FlashCopy SE.
Copying by dataset
If you specify the extent when you establish a relationship, only a part of the volume will be copied.
This is called dataset copying. Dataset copying establishes the relationship only to the specified
extent or extents. You can specify up to 16 target extents per one source extent. To perform dataset
copying, the number of tracks of the copy source extent and the copy target extent must be the
same.
The following list shows the available and unavailable combinations of the extents to establish the
relationships in the case of dataset copying.
Dataset copying can be performed when:
•
The position of the copy source extent is different from the position of the copy target extent.
•
The volume of the copy source extent is different from the volume of the copy target extent.
•
The copy source extent and the copy target extent are in the same volume, provided that they
do not overlap.
•
The data in a single source extent is to be copied simultaneously to multiple target extents.
•
Volume copying is also performed simultaneously in the same sourced volume.
•
Two source extents overlap, or one of them is an inclusive part of the other (see the following
figure), provided that the number of overlapping extents in each overlapped area is not more
than 16 extents.
Figure 4 Overlap of copy source extents
Dataset copying cannot be performed when:
•
Any one of the copy target extents overlaps a copy target extent.
•
Any one of the copy target extents overlaps a copy source extent.
•
A copy target extent that already has a relationship established is used to establish a new
relationship with a copy source or target extent that overlaps.
•
A copy source extent that already has a relationship established is used to establish a new
relationship with a copy target extent that overlaps.
The following table shows the compatibility between the Compatible FlashCopy functions and the
user interface functions.
10 About Compatible FlashCopy operations