Hello,
Yes, each virtual disk can be added as an individual datastore. I'd suggest, instead of installing ESXi on one of those VDs, use a flash drive and leave the VDs for VMs.
All the best,
Mike
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Mike Brown
VMware, Cisco Data Center, and NetApp dude
Consulting Engineer
Twitter: @VirtuallyMikeB
Blog: http://VirtuallyMikeBrown.com
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