2 flashcopy and global copy – IBM DS6000 User Manual

Page 74

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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

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