diff --git a/pkg/cloudprovider/controller/nodecontroller.go b/pkg/cloudprovider/controller/nodecontroller.go
index dc94ce65136..b164ddbef73 100644
--- a/pkg/cloudprovider/controller/nodecontroller.go
+++ b/pkg/cloudprovider/controller/nodecontroller.go
@@ -40,11 +40,6 @@ var (
 	ErrCloudInstance  = errors.New("cloud provider doesn't support instances.")
 )
 
-var (
-	// aliased to allow mocking in tests
-	lookupIP = net.LookupIP
-)
-
 type NodeController struct {
 	cloud              cloudprovider.Interface
 	matchRE            string
@@ -54,6 +49,7 @@ type NodeController struct {
 	kubeletClient      client.KubeletHealthChecker
 	registerRetryCount int
 	podEvictionTimeout time.Duration
+	lookupIP           func(host string) ([]net.IP, error)
 }
 
 // NewNodeController returns a new node controller to sync instances from cloudprovider.
@@ -77,6 +73,7 @@ func NewNodeController(
 		kubeletClient:      kubeletClient,
 		registerRetryCount: registerRetryCount,
 		podEvictionTimeout: podEvictionTimeout,
+		lookupIP:           net.LookupIP,
 	}
 }
 
@@ -289,7 +286,7 @@ func (s *NodeController) PopulateAddresses(nodes *api.NodeList) (*api.NodeList,
 				address := api.NodeAddress{Type: api.NodeLegacyHostIP, Address: addr.String()}
 				api.AddToNodeAddresses(&node.Status.Addresses, address)
 			} else {
-				addrs, err := lookupIP(node.Name)
+				addrs, err := s.lookupIP(node.Name)
 				if err != nil {
 					glog.Errorf("Can't get ip address of node %s: %v", node.Name, err)
 				} else if len(addrs) == 0 {
diff --git a/pkg/cloudprovider/controller/nodecontroller_test.go b/pkg/cloudprovider/controller/nodecontroller_test.go
index c62912601b3..24219d9489d 100644
--- a/pkg/cloudprovider/controller/nodecontroller_test.go
+++ b/pkg/cloudprovider/controller/nodecontroller_test.go
@@ -52,12 +52,6 @@ type FakeNodeHandler struct {
 	RequestCount int
 }
 
-func init() {
-	lookupIP = func(host string) ([]net.IP, error) {
-		return nil, fmt.Errorf("lookup %v: no such host", host)
-	}
-}
-
 func (c *FakeNodeHandler) Nodes() client.NodeInterface {
 	return c
 }
@@ -720,6 +714,9 @@ func TestSyncNodeStatusTransitionTime(t *testing.T) {
 
 	for _, item := range table {
 		nodeController := NewNodeController(nil, "", []string{"node0"}, nil, item.fakeNodeHandler, item.fakeKubeletClient, 10, time.Minute)
+		nodeController.lookupIP = func(host string) ([]net.IP, error) {
+			return nil, fmt.Errorf("lookup %v: no such host", host)
+		}
 		if err := nodeController.SyncNodeStatus(); err != nil {
 			t.Errorf("unexpected error: %v", err)
 		}
@@ -991,6 +988,9 @@ func TestSyncNodeStatusDeletePods(t *testing.T) {
 
 	for _, item := range table {
 		nodeController := NewNodeController(nil, "", []string{"node0"}, nil, item.fakeNodeHandler, item.fakeKubeletClient, 10, 5*time.Minute)
+		nodeController.lookupIP = func(host string) ([]net.IP, error) {
+			return nil, fmt.Errorf("lookup %v: no such host", host)
+		}
 		if err := nodeController.SyncNodeStatus(); err != nil {
 			t.Errorf("unexpected error: %v", err)
 		}