@Catelli that's quite common setup, afaik. Clusters in different locations. I think the biggest challenge there is to do proper networking: ipsec, etc.
@Catelli the nutanix training is been interesting so far: #nutanix is software company/storage company. Running one storage processor in each node. Have you seen PoCs of large MySQL oder Postgres Databases? I wonder how good Nutanix behaves.