9 comparison of versions 1 and 2 – HP StorageWorks XP Remote Web Console Software User Manual
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9 Comparison of Versions 1 and 2
This chapter provides a comparison of FlashCopy Versions 1 and 2.
Version 1 and 2 are different regarding the following functions and usage conditions. Because
Version 1 and 2 cannot co-exist in the same storage system, choose either one based on the
information in the
.
Table 71 Differences Between Version 1 and Version 2
Version 2
Version 1
Compared Item
Additional shared memory may also be
necessary.
No additional shared memory is
required.
Shared memory
S-VOL ≤ T-VOL
S-VOL = T-VOL
Requirement for the capacity of the
S-VOL and T-VOL for a volume copy
operation
Can create pairs with volumes in the
same LSS or different LSS.
Can create pairs with only volumes in
the same LSS.
S-VOL/T-VOL LSS
Can create pairs with the entire source
and target volumes or with the copy
Can create pairs with all source and
target volumes or with the copy source
Range of extents
source and target extents located at the
and target extents that are located at
same or a different position on the
source and target volumes.
the same position on the source and
target volumes.
Pairs are managed by the specified
extents or by the volume when the entire
Pairs are managed by volume. Even
when multiple datasets on the same
Unit used for relationship management
volume is specified. When multiple
volume are specified, the number of
the pair is regarded as 1.
datasets are specified on the same
volume, each dataset is regarded as a
relationship.
Maximum of 16 relationships can be
created with one source extent
(multi-relationship).
One relationship can be created with
one source volume.
Number of relationships created with
a source
You may specify the ShadowImage for
Mainframe volume other than Simplex
You may specify a ShadowImage for
Mainframe volume other than Simplex
Requirements for creating relationships
status for the copy source, but you need
status for the copy source, but you
to specify the Simplex volume for the
copy target (for details, see
).
need to specify the Simplex volume
for the copy target (for details, see
).
Up to 16 Version 2 relationships can
be established by specifying a
A ShadowImage for Mainframe S-VOL
that already forms a pair with three
ShadowImage for Mainframe S-VOL
T-VOLs cannot be specified as the
S-VOL of a Version 1 relationship.
that already forms a pair with three
T-VOLs.
Version 2 can share the volume with
the following program products:
Version 1 can share the volume with
the following program products:
Using with other copy solutions
•
ShadowImage for Mainframe
•
ShadowImage for Mainframe
•
•
TrueCopy for Mainframe (only with
M-VOLs)
TrueCopy for Mainframe (R-VOLs
are also available in some cases)
•
•
Universal Replicator for Mainframe
Universal Replicator for Mainframe
•
•
Compatible XRC
Compatible XRC
•
•
Concurrent Copy
Concurrent Copy
The COPY FULL command is used to
create a Version 2 relationship with the
entire volume.
The COPY FULL command is used to
create a Version 1 relationship with
the entire volume.
DFSMSdss
command
140 Comparison of Versions 1 and 2