To load balance the data coming through NMSP from the WLCs and spread the load between multiple CMX servers, the configuration cmxctl config feature flags nmsplb.cmx-ap-grouping true should be used. This enables the load balancing feature and helps optimize the data flow for APs in a large network environment. References: The configuration for load balancing in CMX is explained in the certification guide, which outlines the commands and flags necessary to manage data flow efficiently.