It works, it is supported (as, IBM Support will support it) and is the normal way to do it. We have used this setup for 12+ years as we ditched all internal disks and storage options on the POWER servers around that time - and it is a waste of PCI slots or HBA ports to dedicate ports to VIOS disks.
It can be a consideration for hybrid NPIV/SSP setups where pure bandwidth/IOPS scaling is needed, but that is a normal I/O design consideration.
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Morten Torstensen
TietoEVRY
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