vSphere Host Profiles help you publish configuration standards across clusters of ESXi hosts. However, every host will have a set of unique settings which needs to be customized as well. When you attach ESXi hosts to a Host Profile, you will be allowed to customize the hosts that are being added. However, if you are dealing with a large set of hosts, supplying the values through the Attach/Detach Host and Clusters wizard will be a laborious task. An alternative and efficient method would be to prepare a  customizations (.csv) file with the host-specific values and use it to perform the host customization. 

The following flow chart provides a high-level overview of the procedure: