Good Post by Hu Yoshida (thank you)
In June of last year 2013, VMware announced VSAN. VMware Virtual SAN is embedded in the VMware vSphere kernel and enables clusters of servers with direct attached hard disk drives and solid state drives (HDD and SSD) to create a shared datastore. The management architecture of VSAN enables administrators to specify storage attributes, such as capacity, performance, and availability, in the form of policies on a per VM basis.
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