VSAN cluster expansion
In addition to the online addition and subtraction of disks in VSAN, nodes can be added and subtracted online. If you wish to add more nodes to an existing VSAN cluster (a scale-out operation), the procedure is not profoundly different to the initial setup process. Once a node is added, the VSAN cluster has been expanded, and new provisioning can immediately make use of the new capacity. Storage capacity load-balancing will occur over time. vSphere DRS and HA can also make immediate use of the new node for resource scheduling and failure recovery.
Adding a node to the VSAN cluster
Once you have acquired the new hardware and installed ESXi, you simply to need to add the host to the vCenter datacenter. Then, create a vmkernel network interface for the new node and tag it for use by VSAN (see the Configure VSAN Networking recipes in Chapter 2, Initial Configuration and Validation of Your VSAN Cluster). If necessary, tag SSDs (see the Tagging disks as local solid-state...