Tls: &networking.ClientTLSSettings{Mode: networking.ClientTLSSettings_MUTUAL},
				},
			},
			expectedSubsetClusters: []*cluster.Cluster{},
		},
		{
			name:        "destination rule with tls mode ISTIO_MUTUAL",
			cluster:     &cluster.Cluster{Name: "foo", ClusterDiscoveryType: &cluster.Cluster_Type{Type: cluster.Cluster_EDS}},
			clusterMode: DefaultClusterMode,
			service:     service,
			port:        servicePort[0],

		out.Mode = istio.ServerTLSSettings_SIMPLE
		if tls.Options != nil {
			switch tls.Options[gatewayTLSTerminateModeKey] {
			case "MUTUAL":
				out.Mode = istio.ServerTLSSettings_MUTUAL
			case "ISTIO_MUTUAL":
				out.Mode = istio.ServerTLSSettings_ISTIO_MUTUAL
				return out, nil
			}
		}
		if len(tls.CertificateRefs) != 1 {
			// This is required in the API, should be rejected in validation