Good Post by Heino Skoy (thank you)
Lately, I’ve been working on a project for a customer, who needed to deploy a vSphere Metro Storage Cluster (vMSC) solution based on vSphere 5.5 and HP 3PAR StoreServ arrays to allow for site failover and improved disaster avoidance.
HP 3PAR StoreServ arrays supports a Uniform vMSC using 3PAR Peer Persistence, meaning that ESXi hosts within the vMSC cluster have access to storage arrays in both sites. See the following illustration for Uniform vMSC cluster architecture:
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