I sent the same query to Diskcore, but it' s may be better to put here.
We are now going to propose to use Subchannel set 1 for DS8K GM B volumes and Subchannel set 2 for thin provisioned GM C volumes in DS8950Fs due to the address constraint in a DR systems. The customer will have D volumes defined as Subchannel set 0, which are used for their DR systems. They are now managing GM with old DS8886s via their own created TSO scripts and they have a plan to expand their GM A volumes and they will use them in the new DS8950F environment too. I believe it's no problem to use the subchannel set 1 or 2 for GM B volumes, but I'd like to confirm and would like to know any consideration if you have experienced. I tested at our lab that it works and we can FlashCopy FRR, etc with subchannel set 1 and 2 environment, but it seems to me that GDPS/GM doesn't support to use subchannel set 1/2/3 for GM B volumes. So, I'd like to check.
Warm regards,
Shin
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SHIN TAKATA
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