InformationSetup TLS connection on the API server.
API server communication contains sensitive parameters that should remain encrypted in transit. Configure the API server to serve only HTTPS traffic. If '--client-ca-file' argument is set, any request presenting a client certificate signed by one of the authorities in the 'client-ca-file' is authenticated with an identity corresponding to the CommonName of the client certificate.
SolutionFollow the Kubernetes documentation and set up the TLS connection on the apiserver. Then, edit the API server pod specification file '/etc/kubernetes/manifests/kube-apiserver.yaml' on the master node and set the client certificate authority file.
TLS and client certificate authentication must be configured for your Kubernetes cluster deployment.