VxRail nodes running vSAN Express Storage Architecture, which was introduced in vSAN 8.0, are enclosed in a one-node, single-server system running dual-core processors with all NVMe mixed-use drives. The nodes form a networked cluster with a minimum of two nodes. Like the VxRail nodes running vSAN OSA, the first two (if a 2-node cluster) or three nodes must have identical configuration and base networking. Unlike the VxRail nodes running vSAN OSA, the homogeneity extends to the restriction of mixing different VxRail series and drive capacities.
vSAN ESA provides significant performance gains compared to vSAN OSA. Clusters running vSAN ESA requires a minimum of 25 GbE base networking with a minimum of 512 GB of memory. Running vSAN ESA also requires vSAN Advanced license edition or higher.