diff --git a/pkg/runtime/kubernetes/certs.go b/pkg/runtime/kubernetes/certs.go
index a39efb0c509..9a14e8cc974 100644
--- a/pkg/runtime/kubernetes/certs.go
+++ b/pkg/runtime/kubernetes/certs.go
@@ -144,7 +144,7 @@ func (k *KubeadmRuntime) initCert() error {
 
 func (k *KubeadmRuntime) syncCert() error {
 	return k.runPipelines("sync all masters cert", func() error {
-		for _, master := range k.getMasterIPList()[1:] {
+		for _, master := range k.getMasterIPAndPortList()[1:] {
 			logger.Debug("start to generate cert for master %s", master)
 			err := k.execCert(master)
 			if err != nil {