For expansion of existing Cisco Hyperflex cluster it is very important to pay attention to the BOM / Configuration, especially the drives. Note that the estimates created via the Cisco Commerce website (CCW) checks for a valid configuration of the initial cluster. However, when ordering expansion nodes, CCW checks do not work, because CCW does not have any information about the drives previously ordered. This document is intended to communicate the compatibility of drives when expanding the cluster either through addition of new nodes or by adding data drives to existing nodes.