The Elemental operator extends Rancher introducing OS provisioning and management capabilities.
Machines booting from an Elemental live ISO register to the Elemental Operator, get provisioned with the OS and a k8s distro, forming a new Kubernetes cluster immediately available in Rancher.
See the Elemental docs for more information.
The Elemental operator should be installed on a K8s cluster running Rancher Multi Cluster Management server.
A step by step guide is available in the official documentation.