c.volumeMounts[component] = map[string]v1.VolumeMount{}
	}
	c.volumeMounts[component][volMount.Name] = volMount
}

// getEtcdCertVolumes returns the volumes/volumemounts needed for talking to an external etcd cluster
func getEtcdCertVolumes(etcdCfg *kubeadmapi.ExternalEtcd, k8sCertificatesDir string) ([]v1.Volume, []v1.VolumeMount) {
	certPaths := []string{etcdCfg.CAFile, etcdCfg.CertFile, etcdCfg.KeyFile}

	for _, rt := range tests {
		t.Run(rt.name, func(t *testing.T) {
			actualVol, actualVolMount := getEtcdCertVolumes(&kubeadmapi.ExternalEtcd{
				CAFile:   rt.ca,
				CertFile: rt.cert,
				KeyFile:  rt.key,
			}, k8sCertificatesDir)
			if !reflect.DeepEqual(actualVol, rt.vol) {
				t.Errorf(
					"failed getEtcdCertVolumes:\n\texpected: %v\n\t  actual: %v",
					rt.vol,
					actualVol,
				)
			}