Connectivity Verification from side car to istio pilot for mTLS enabled policy fails

As mentioned in the page to verify connectivity between sidecar envoy and istio pilot , i performed below test

  1. Logged in to istio-ingress gateway pod

kubectl exec -it istio-ingressgateway-58447cfc87-mxgjl -n istio-system /bin/bash

  1. Tried curl commnad from istio-ingress gateway pod to istio-pilot with all certificates as mentioned in below command
    root@istio-ingressgateway-58447cfc87-mxgjl:/# curl -k --cert /etc/certs/cert-chain.pem --cacert /etc/certs/root-cert.pem --key /etc/certs/key.pem https://istio-pilot:8080/debug/edsz
    curl: (35) gnutls_handshake() failed: An unexpected TLS packet was received.

And I am getting error message as shown above highlighted in bold.

Does any one have idea what could be wrong?