IBM System storage DS6000 Series, Redbook

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IBM System Storage DS6000 Series: Copy Services with IBM System z
– If you create the FlashCopy first and then do a Metro Mirror of the FlashCopy target,
you must monitor the progress of the FlashCopy background copy. In this case the
following considerations apply:
• The Metro Mirror secondary will not be in a fully consistent state until the FlashCopy
background copy process is complete.
• Use the
copy
option to ensure that the entire FlashCopy source volume data is
copied to the Metro Mirror secondary.
On the secondary site of the Metro Mirror, a FlashCopy
source volume
can be the Metro
Mirror
secondary volume
and vice versa. There are no restrictions on which relationship
should be defined first.
6.4.2 FlashCopy and Global Copy
Figure 6-8 FlashCopy and Global Copy
As illustrated in Figure 6-8, at the primary Global Copy site the following combinations are
possible:
򐂰 A FlashCopy
source volume
can become a Global Copy
primary volume
and vice versa.
The order of creation is optional.
򐂰 A FlashCopy
target volume
can become a Global Copy
primary volume
and vice versa. If
you wish to use a FlashCopy target volume as a Global Copy primary, be aware of the
following considerations:
– The recommended order is to first establish the Global Copy, and then create a
FlashCopy to that Global Copy primary using the -tgtpprc parameter if using DS CLI,
or TGTPPRIM(YES) if using TSO, or PPRCPRIM(YES) if using ICKDSF, or
FCTOPPRCPrimary if using DFSMSdss.
The Global Copy secondary will not be in a fully consistent state until the Global Copy
is forced to the full duplex state.
– If you create the FlashCopy first, and then do a Global Copy of the FlashCopy target,
you must monitor the progress of the FlashCopy background copy.
source
target
FlashCopy
Global
Copy
primary
secondary primary
Global
Copy
source
target
FlashCopy