Profile applicability: Level 1 - Master Node
etcd should be configured to make use of TLS encryption for client connections.
etcd is a highly-available key value store used by Kubernetes deployments for persistent
               storage of all of its REST API objects. These objects are sensitive in nature and
               should be
               protected by client authentication. This requires the API server to identify itself
               to the etcd
               server using a client certificate and key.
NoteBy default,  
--etcd-certfile and --etcd-keyfile arguments are
                              not set. | 
Impact
TLS and client certificate authentication must be configured for etcd.
Audit
Run the following command on the Control Plane node:
ps -ef | grep kube-apiserver
Verify that the 
--etcd-certfile and --etcd-keyfile arguments
                  exist and they are set as appropriate.Remediation
Follow the Kubernetes documentation and set up the TLS connection between the apiserver
                  and
                  etcd. Then, edit the API server pod specification file
                  
/etc/kubernetes/manifests/kube-apiserver.yaml on the master node and set the
                  etcd certificate and key file parameters.--etcd-certfile=<path/to/client-certificate-file> --etcd-keyfile=<path/to/client-key-file>
		