East-West can be done (for a small number of servers) with direct links, no switch. They seem to still require highly capable North-South switches. Perhaps for fast & robust failover of N-S traffic and bandwidth sharing? Physical network requirements for Azure Stack HCI - Azure Stack HCI | Microsoft Docs ... View more

Indeed, though MS is pushing Azure HCI as a branch-office convergence approach requiring just two physical servers and (ahem) PFC. ... View more