diff --git a/tools/gate/kubeadm/funcs/network.sh b/tools/gate/kubeadm/funcs/network.sh
index 9f22a5d7..10b1b7f6 100644
--- a/tools/gate/kubeadm/funcs/network.sh
+++ b/tools/gate/kubeadm/funcs/network.sh
@@ -26,8 +26,7 @@ function net_default_host_ip {
 
 function net_resolv_pre_kube {
   sudo cp -f /etc/resolv.conf /etc/resolv-pre-kube.conf
-  sudo rm -f /etc/resolv.conf
-  cat << EOF | sudo tee /etc/resolv.conf
+  cat << EOF | sudo tee -a /etc/resolv.conf
 nameserver ${UPSTREAM_DNS}
 EOF
 }