Stateless hosts do not persist configuration, so they need an auto-deploy server to provide the required start files when hosts power on.
This section helps you to set up a stateless cluster using vSphere Auto Deploy and NSX Transport Node Profile to reprovision a host with a new image profile that contains a different version of ESXi and NSX. Hosts that are set up for vSphere Auto Deploy use an auto-deploy server and vSphere host profiles to customize hosts. These hosts can also be set up for NSX Transport Node Profile to configure NSX on the hosts.
So, a stateless host can be set up for vSphere Auto Deploy and NSX Transport Node Profile to reprovision a host with a custom ESXi and NSX version.