HP StorageWorks XP Remote Web Console Software - Manual (Page 146)

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
“Differences Between Version 1 and Version 2” (page 146) .
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
source and target extents located at the
same or a different position on the
source and target volumes. Can create pairs with all source and
target volumes or with the copy source
and target extents that are located at
the same position on the source and
target volumes. Range of extents
Pairs are managed by the specified
extents or by the volume when the entire
volume is specified. When multiple
datasets are specified on the same
volume, each dataset is regarded as a
relationship. Pairs are managed by volume. Even
when multiple datasets on the same
volume are specified, the number of
the pair is regarded as 1. Unit used for relationship management
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
status for the copy source, but you need
to specify the Simplex volume for the
copy target (for details, see
“Using
Version 2 with ShadowImage for
Mainframe” (page 54)
).
Up to 16 Version 2 relationships can
be established by specifying a
ShadowImage for Mainframe S-VOL
that already forms a pair with three
T-VOLs.
You may specify a ShadowImage for
Mainframe volume other than Simplex
status for the copy source, but you
need to specify the Simplex volume
for the copy target (for details, see
“Using Version 1 with ShadowImage
for Mainframe” (page 9)
).
A ShadowImage for Mainframe S-VOL
that already forms a pair with three
T-VOLs cannot be specified as the
S-VOL of a Version 1 relationship.
Requirements for creating relationships
Version 2 can share the volume with
the following program products:
• ShadowImage for Mainframe
•
TrueCopy for Mainframe (R-VOLs
are also available in some cases)
• Universal Replicator for Mainframe
•
Compatible XRC
•
Concurrent Copy
Version 1 can share the volume with
the following program products:
• ShadowImage for Mainframe
•
TrueCopy for Mainframe (only with
M-VOLs)
• Universal Replicator for Mainframe
•
Compatible XRC
•
Concurrent Copy
Using with other copy solutions
146 Comparison of Versions 1 and 2