HP StorageWorks XP24000 for FlashCopy Mirroring Software User's Guide (T5240-96001, June 2007)

you select NOCOPY mode, you must withdraw the pair by using the FCWITHDR command. For details
about the FCW ITHDR command, see “Releasing a Version 2 Relationship Using FCWITHDR” on page 83.
Copy ing by Volume
If you do not specify the extent when you establish a relationship, the whole volume will be copied. This
is
called volume copying. Note that to per form volume copyi ng, the capacity of the copy source volume
must be equal to or larger than the capacity of the copy target volume.
Copy ing by Dataset
If you specify an 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, and you can specify up to 16 target extents per 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 for dataset copying.
• Version 2 can per form dataset copying 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 asinglesource extentistobecopiedsimultaneouslytomultipletargetextents.
• 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
Figure 16 on page 45), provided that the number of overlapping extents in each overlapped
area is not more than 16 extents.
S-VOL
T-VOL
Figure
16 Overlap of Copy Source Extents
• Version 2 ca nnot perform dataset copying when:
• Any one of the copy target extents is overlapping a copy source or target extent.
•A copy
target extent that already has a relationship established is used to establish a new
relationship with a co py source or target extent that overlaps.
Table 19 on page 46 shows the compatibility between the Version 2 functions and the user interface
functions.
XP24000 for FlashCopy Mirroring Software User's Guide
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