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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