Remove Node Controllers ability to pull status from Kubelet

cmd/integration/integration.go

@@ -224,7 +224,7 @@ func startComponents(firstManifestURL, secondManifestURL, apiVersion string) (st
 		}}
 
 	nodeController := nodeControllerPkg.NewNodeController(nil, "", machineList, nodeResources, cl, fakeKubeletClient{}, 10, 5*time.Minute, util.NewFakeRateLimiter(), 40*time.Second, 60*time.Second, 5*time.Second)
-	nodeController.Run(5*time.Second, true, false)
+	nodeController.Run(5*time.Second, true)
 	cadvisorInterface := new(cadvisor.Fake)
 
 	// Kubelet (localhost)

cmd/kube-controller-manager/app/controllermanager.go

@@ -86,7 +86,6 @@ func NewCMServer() *CMServer {
 		NodeMilliCPU:            1000,
 		NodeMemory:              resource.MustParse("3Gi"),
 		SyncNodeList:            true,
-		SyncNodeStatus:          false,
 		KubeletConfig: client.KubeletConfig{
 			Port:        ports.KubeletPort,
 			EnableHttps: true,
@@ -116,13 +115,16 @@ func (s *CMServer) AddFlags(fs *pflag.FlagSet) {
 		"The number of retries for initial node registration.  Retry interval equals node_sync_period.")
 	fs.Var(&s.MachineList, "machines", "List of machines to schedule onto, comma separated.")
 	fs.BoolVar(&s.SyncNodeList, "sync_nodes", s.SyncNodeList, "If true, and --cloud_provider is specified, sync nodes from the cloud provider. Default true.")
-	fs.BoolVar(&s.SyncNodeStatus, "sync_node_status", s.SyncNodeStatus, ""+
-		"If true, node controller sends probes to kubelet and updates NodeStatus."+
-		"If false, Kubelet posts NodeStatus to API server.")
-	fs.DurationVar(&s.NodeMonitorGracePeriod, "node_monitor_grace_period", 40*time.Second, "Amount of time which we allow running Node to be unresponsive before marking it unhealty."+
-		"Must be N times more than kubelet's nodeStatusUpdateFrequency, where N means number of retries allowed for kubelet to post node status.")
-	fs.DurationVar(&s.NodeStartupGracePeriod, "node_startup_grace_period", 60*time.Second, "Amount of time which we allow starting Node to be unresponsive before marking it unhealty.")
-	fs.DurationVar(&s.NodeMonitorPeriod, "node_monitor_period", 5*time.Second, "The period for syncing NodeStatus in NodeController.")
+	fs.BoolVar(&s.SyncNodeStatus, "sync_node_status", s.SyncNodeStatus,
+		"DEPRECATED. Does not have any effect now and it will be removed in a later release.")
+	fs.DurationVar(&s.NodeMonitorGracePeriod, "node_monitor_grace_period", 40*time.Second,
+		"Amount of time which we allow running Node to be unresponsive before marking it unhealty. "+
+			"Must be N times more than kubelet's nodeStatusUpdateFrequency, "+
+			"where N means number of retries allowed for kubelet to post node status.")
+	fs.DurationVar(&s.NodeStartupGracePeriod, "node_startup_grace_period", 60*time.Second,
+		"Amount of time which we allow starting Node to be unresponsive before marking it unhealty.")
+	fs.DurationVar(&s.NodeMonitorPeriod, "node_monitor_period", 5*time.Second,
+		"The period for syncing NodeStatus in NodeController.")
 	// TODO: Discover these by pinging the host machines, and rip out these flags.
 	// TODO: in the meantime, use resource.QuantityFlag() instead of these
 	fs.Int64Var(&s.NodeMilliCPU, "node_milli_cpu", s.NodeMilliCPU, "The amount of MilliCPU provisioned on each node")
@@ -188,10 +190,14 @@ func (s *CMServer) Run(_ []string) error {
 		},
 	}
 
+	if s.SyncNodeStatus {
+		glog.Warning("DEPRECATION NOTICE: sync_node_status flag is being deprecated. It has no effect now and it will be removed in a future version.")
+	}
+
 	nodeController := nodeControllerPkg.NewNodeController(cloud, s.MinionRegexp, s.MachineList, nodeResources,
 		kubeClient, kubeletClient, s.RegisterRetryCount, s.PodEvictionTimeout, util.NewTokenBucketRateLimiter(s.DeletingPodsQps, s.DeletingPodsBurst),
 		s.NodeMonitorGracePeriod, s.NodeStartupGracePeriod, s.NodeMonitorPeriod)
-	nodeController.Run(s.NodeSyncPeriod, s.SyncNodeList, s.SyncNodeStatus)
+	nodeController.Run(s.NodeSyncPeriod, s.SyncNodeList)
 
 	resourceQuotaManager := resourcequota.NewResourceQuotaManager(kubeClient)
 	resourceQuotaManager.Run(s.ResourceQuotaSyncPeriod)

cmd/kubernetes/kubernetes.go

@@ -132,7 +132,7 @@ func runControllerManager(machineList []string, cl *client.Client, nodeMilliCPU,
 
 	nodeController := nodeControllerPkg.NewNodeController(
 		nil, "", machineList, nodeResources, cl, kubeClient, 10, 5*time.Minute, util.NewTokenBucketRateLimiter(*deletingPodsQps, *deletingPodsBurst), 40*time.Second, 60*time.Second, 5*time.Second)
-	nodeController.Run(10*time.Second, true, true)
+	nodeController.Run(10*time.Second, true)
 
 	endpoints := service.NewEndpointController(cl)
 	go util.Forever(func() { endpoints.SyncServiceEndpoints() }, time.Second*10)

pkg/api/types.go

@@ -1113,7 +1113,7 @@ const (
 type NodeCondition struct {
 	Type               NodeConditionType `json:"type"`
 	Status             ConditionStatus   `json:"status"`
-	LastProbeTime      util.Time         `json:"lastProbeTime,omitempty"`
+	LastHeartbeatTime  util.Time         `json:"lastHeartbeatTime,omitempty"`
 	LastTransitionTime util.Time         `json:"lastTransitionTime,omitempty"`
 	Reason             string            `json:"reason,omitempty"`
 	Message            string            `json:"message,omitempty"`

pkg/api/v1beta1/conversion.go

@@ -1369,7 +1369,7 @@ func init() {
 			if err := s.Convert(&in.Status, &out.Status, 0); err != nil {
 				return err
 			}
-			if err := s.Convert(&in.LastProbeTime, &out.LastProbeTime, 0); err != nil {
+			if err := s.Convert(&in.LastHeartbeatTime, &out.LastProbeTime, 0); err != nil {
 				return err
 			}
 			if err := s.Convert(&in.LastTransitionTime, &out.LastTransitionTime, 0); err != nil {
@@ -1390,7 +1390,7 @@ func init() {
 			if err := s.Convert(&in.Status, &out.Status, 0); err != nil {
 				return err
 			}
-			if err := s.Convert(&in.LastProbeTime, &out.LastProbeTime, 0); err != nil {
+			if err := s.Convert(&in.LastProbeTime, &out.LastHeartbeatTime, 0); err != nil {
 				return err
 			}
 			if err := s.Convert(&in.LastTransitionTime, &out.LastTransitionTime, 0); err != nil {

pkg/api/v1beta2/conversion.go

@@ -1296,7 +1296,7 @@ func init() {
 			if err := s.Convert(&in.Status, &out.Status, 0); err != nil {
 				return err
 			}
-			if err := s.Convert(&in.LastProbeTime, &out.LastProbeTime, 0); err != nil {
+			if err := s.Convert(&in.LastHeartbeatTime, &out.LastProbeTime, 0); err != nil {
 				return err
 			}
 			if err := s.Convert(&in.LastTransitionTime, &out.LastTransitionTime, 0); err != nil {
@@ -1317,7 +1317,7 @@ func init() {
 			if err := s.Convert(&in.Status, &out.Status, 0); err != nil {
 				return err
 			}
-			if err := s.Convert(&in.LastProbeTime, &out.LastProbeTime, 0); err != nil {
+			if err := s.Convert(&in.LastProbeTime, &out.LastHeartbeatTime, 0); err != nil {
 				return err
 			}
 			if err := s.Convert(&in.LastTransitionTime, &out.LastTransitionTime, 0); err != nil {

pkg/api/v1beta3/types.go

@@ -1110,7 +1110,7 @@ const (
 type NodeCondition struct {
 	Type               NodeConditionType `json:"type" description:"type of node condition, one of Ready, Schedulable"`
 	Status             ConditionStatus   `json:"status" description:"status of the condition, one of Full, None, Unknown"`
-	LastProbeTime      util.Time         `json:"lastProbeTime,omitempty" description:"last time the condition was probed"`
+	LastHeartbeatTime  util.Time         `json:"lastHeartbeatTime,omitempty" description:"last time we got an update on a given condition"`
 	LastTransitionTime util.Time         `json:"lastTransitionTime,omitempty" description:"last time the condition transit from one status to another"`
 	Reason             string            `json:"reason,omitempty" description:"(brief) reason for the condition's last transition"`
 	Message            string            `json:"message,omitempty" description:"human readable message indicating details about last transition"`

pkg/cloudprovider/controller/nodecontroller.go

@@ -21,7 +21,6 @@ import (
 	"fmt"
 	"net"
 	"strings"
-	"sync"
 	"time"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
@@ -29,7 +28,6 @@ import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/cloudprovider"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/labels"
-	"github.com/GoogleCloudPlatform/kubernetes/pkg/probe"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
 	"github.com/golang/glog"
 )
@@ -132,12 +130,9 @@ func NewNodeController(
 //    node addresses.
 // 2. SyncCloudNodes() is called periodically (if enabled) to sync instances from cloudprovider.
 //    Node created here will only have specs.
-// 3. Depending on how k8s is configured, there are two ways of syncing the node status:
-//   3.1 SyncProbedNodeStatus() is called periodically to trigger master to probe kubelet,
-//       and incorporate the resulting node status.
-//   3.2 MonitorNodeStatus() is called periodically to incorporate the results of node status
+// 3. MonitorNodeStatus() is called periodically to incorporate the results of node status
 //    pushed from kubelet to master.
-func (nc *NodeController) Run(period time.Duration, syncNodeList, syncNodeStatus bool) {
+func (nc *NodeController) Run(period time.Duration, syncNodeList bool) {
 	// Register intial set of nodes with their status set.
 	var nodes *api.NodeList
 	var err error
@@ -170,20 +165,12 @@ func (nc *NodeController) Run(period time.Duration, syncNodeList, syncNodeStatus
 		}, period)
 	}
 
-	// Start syncing or monitoring node status.
-	if syncNodeStatus {
+	// Start monitoring node status.
 	go util.Forever(func() {
-			if err := nc.SyncProbedNodeStatus(); err != nil {
-				glog.Errorf("Error syncing status: %v", err)
-			}
-		}, period)
-	} else {
-		go util.Forever(func() {
-			if err := nc.MonitorNodeStatus(); err != nil {
+		if err = nc.MonitorNodeStatus(); err != nil {
 			glog.Errorf("Error monitoring node status: %v", err)
 		}
 	}, nc.nodeMonitorPeriod)
-	}
 }
 
 // RegisterNodes registers the given list of nodes, it keeps retrying for `retryCount` times.
@@ -272,121 +259,6 @@ func (nc *NodeController) SyncCloudNodes() error {
 	return nil
 }
 
-// SyncProbedNodeStatus synchronizes cluster nodes status to master server.
-func (nc *NodeController) SyncProbedNodeStatus() error {
-	nodes, err := nc.kubeClient.Nodes().List()
-	if err != nil {
-		return err
-	}
-	nodes, err = nc.PopulateNodesStatus(nodes)
-	if err != nil {
-		return err
-	}
-	for _, node := range nodes.Items {
-		// We used to skip updating node when node status doesn't change, this is no longer
-		// useful after we introduce per-probe status field, e.g. 'LastProbeTime', which will
-		// differ in every call of the sync loop.
-		glog.V(2).Infof("updating node %v", node.Name)
-		_, err = nc.kubeClient.Nodes().Update(&node)
-		if err != nil {
-			glog.Errorf("error updating node %s: %v", node.Name, err)
-		}
-	}
-	return nil
-}
-
-// PopulateNodesStatus populates node status for given list of nodes.
-func (nc *NodeController) PopulateNodesStatus(nodes *api.NodeList) (*api.NodeList, error) {
-	var wg sync.WaitGroup
-	wg.Add(len(nodes.Items))
-	for i := range nodes.Items {
-		go func(node *api.Node) {
-			node.Status.Conditions = nc.DoCheck(node)
-			if err := nc.populateNodeInfo(node); err != nil {
-				glog.Errorf("Can't collect information for node %s: %v", node.Name, err)
-			}
-			wg.Done()
-		}(&nodes.Items[i])
-	}
-	wg.Wait()
-	return nc.PopulateAddresses(nodes)
-}
-
-// populateNodeInfo gets node info from kubelet and update the node.
-func (nc *NodeController) populateNodeInfo(node *api.Node) error {
-	nodeInfo, err := nc.kubeletClient.GetNodeInfo(node.Name)
-	if err != nil {
-		return err
-	}
-	for key, value := range nodeInfo.Capacity {
-		node.Status.Capacity[key] = value
-	}
-	node.Status.NodeInfo = nodeInfo.NodeSystemInfo
-	return nil
-}
-
-// DoCheck performs various condition checks for given node.
-func (nc *NodeController) DoCheck(node *api.Node) []api.NodeCondition {
-	var conditions []api.NodeCondition
-
-	// Check Condition: NodeReady. TODO: More node conditions.
-	oldReadyCondition := nc.getCondition(&node.Status, api.NodeReady)
-	newReadyCondition := nc.checkNodeReady(node)
-	nc.updateLastTransitionTime(oldReadyCondition, newReadyCondition)
-	if newReadyCondition.Status != api.ConditionTrue {
-		// Node is not ready for this probe, we need to check if pods need to be deleted.
-		if newReadyCondition.LastProbeTime.After(newReadyCondition.LastTransitionTime.Add(nc.podEvictionTimeout)) {
-			// As long as the node fails, we call delete pods to delete all pods. Node controller sync
-			// is not a closed loop process, there is no feedback from other components regarding pod
-			// status. Keep listing pods to sanity check if pods are all deleted makes more sense.
-			nc.deletePods(node.Name)
-		}
-	}
-	conditions = append(conditions, *newReadyCondition)
-
-	return conditions
-}
-
-// updateLastTransitionTime updates LastTransitionTime for the newCondition based on oldCondition.
-func (nc *NodeController) updateLastTransitionTime(oldCondition, newCondition *api.NodeCondition) {
-	if oldCondition != nil && oldCondition.Status == newCondition.Status {
-		// If node status doesn't change, transition time is same as last time.
-		newCondition.LastTransitionTime = oldCondition.LastTransitionTime
-	} else {
-		// Set transition time to Now() if node status changes or `oldCondition` is nil, which
-		// happens only when the node is checked for the first time.
-		newCondition.LastTransitionTime = nc.now()
-	}
-}
-
-// checkNodeReady checks raw node ready condition, without transition timestamp set.
-func (nc *NodeController) checkNodeReady(node *api.Node) *api.NodeCondition {
-	switch status, err := nc.kubeletClient.HealthCheck(node.Name); {
-	case err != nil:
-		glog.V(2).Infof("NodeController: node %s health check error: %v", node.Name, err)
-		return &api.NodeCondition{
-			Type:          api.NodeReady,
-			Status:        api.ConditionUnknown,
-			Reason:        fmt.Sprintf("Node health check error: %v", err),
-			LastProbeTime: nc.now(),
-		}
-	case status == probe.Failure:
-		return &api.NodeCondition{
-			Type:          api.NodeReady,
-			Status:        api.ConditionFalse,
-			Reason:        fmt.Sprintf("Node health check failed: kubelet /healthz endpoint returns not ok"),
-			LastProbeTime: nc.now(),
-		}
-	default:
-		return &api.NodeCondition{
-			Type:          api.NodeReady,
-			Status:        api.ConditionTrue,
-			Reason:        fmt.Sprintf("Node health check succeeded: kubelet /healthz endpoint returns ok"),
-			LastProbeTime: nc.now(),
-		}
-	}
-}
-
 // PopulateAddresses queries Address for given list of nodes.
 func (nc *NodeController) PopulateAddresses(nodes *api.NodeList) (*api.NodeList, error) {
 	if nc.isRunningCloudProvider() {
@@ -440,7 +312,7 @@ func (nc *NodeController) tryUpdateNodeStatus(node *api.Node) (time.Duration, ap
 		lastReadyCondition = api.NodeCondition{
 			Type:               api.NodeReady,
 			Status:             api.ConditionUnknown,
-			LastProbeTime:      node.CreationTimestamp,
+			LastHeartbeatTime:  node.CreationTimestamp,
 			LastTransitionTime: node.CreationTimestamp,
 		}
 		gracePeriod = nc.nodeStartupGracePeriod
@@ -497,7 +369,7 @@ func (nc *NodeController) tryUpdateNodeStatus(node *api.Node) (time.Duration, ap
 			readyTransitionTimestamp: nc.now(),
 		}
 		nc.nodeStatusMap[node.Name] = savedNodeStatus
-	} else if savedCondition != nil && observedCondition != nil && savedCondition.LastProbeTime != observedCondition.LastProbeTime {
+	} else if savedCondition != nil && observedCondition != nil && savedCondition.LastHeartbeatTime != observedCondition.LastHeartbeatTime {
 		var transitionTime util.Time
 		// If ReadyCondition changed since the last time we checked, we update the transition timestamp to "now",
 		// otherwise we leave it as it is.
@@ -526,7 +398,7 @@ func (nc *NodeController) tryUpdateNodeStatus(node *api.Node) (time.Duration, ap
 				Type:               api.NodeReady,
 				Status:             api.ConditionUnknown,
 				Reason:             fmt.Sprintf("Kubelet never posted node status."),
-				LastProbeTime:      node.CreationTimestamp,
+				LastHeartbeatTime:  node.CreationTimestamp,
 				LastTransitionTime: nc.now(),
 			})
 		} else {
@@ -536,7 +408,7 @@ func (nc *NodeController) tryUpdateNodeStatus(node *api.Node) (time.Duration, ap
 				readyCondition.Status = api.ConditionUnknown
 				readyCondition.Reason = fmt.Sprintf("Kubelet stopped posting node status.")
 				// LastProbeTime is the last time we heard from kubelet.
-				readyCondition.LastProbeTime = lastReadyCondition.LastProbeTime
+				readyCondition.LastHeartbeatTime = lastReadyCondition.LastHeartbeatTime
 				readyCondition.LastTransitionTime = nc.now()
 			}
 		}

pkg/kubectl/describe.go

@@ -496,12 +496,12 @@ func describeNode(node *api.Node, pods []api.Pod, events *api.EventList) (string
 		fmt.Fprintf(out, "Labels:\t%s\n", formatLabels(node.Labels))
 		fmt.Fprintf(out, "CreationTimestamp:\t%s\n", node.CreationTimestamp.Time.Format(time.RFC1123Z))
 		if len(node.Status.Conditions) > 0 {
-			fmt.Fprint(out, "Conditions:\n  Type\tStatus\tLastProbeTime\tLastTransitionTime\tReason\tMessage\n")
+			fmt.Fprint(out, "Conditions:\n  Type\tStatus\tLastHeartbeatTime\tLastTransitionTime\tReason\tMessage\n")
 			for _, c := range node.Status.Conditions {
 				fmt.Fprintf(out, "  %v \t%v \t%s \t%s \t%v \t%v\n",
 					c.Type,
 					c.Status,
-					c.LastProbeTime.Time.Format(time.RFC1123Z),
+					c.LastHeartbeatTime.Time.Format(time.RFC1123Z),
 					c.LastTransitionTime.Time.Format(time.RFC1123Z),
 					c.Reason,
 					c.Message)

pkg/kubelet/kubelet.go

@@ -1810,7 +1810,7 @@ func (kl *Kubelet) tryUpdateNodeStatus() error {
 		Type:              api.NodeReady,
 		Status:            api.ConditionTrue,
 		Reason:            fmt.Sprintf("kubelet is posting ready status"),
-		LastProbeTime: currentTime,
+		LastHeartbeatTime: currentTime,
 	}
 	updated := false
 	for i := range node.Status.Conditions {

pkg/kubelet/kubelet_test.go

@@ -3080,7 +3080,7 @@ func TestUpdateNewNodeStatus(t *testing.T) {
 					Type:               api.NodeReady,
 					Status:             api.ConditionTrue,
 					Reason:             fmt.Sprintf("kubelet is posting ready status"),
-					LastProbeTime:      util.Time{},
+					LastHeartbeatTime:  util.Time{},
 					LastTransitionTime: util.Time{},
 				},
 			},
@@ -3111,13 +3111,13 @@ func TestUpdateNewNodeStatus(t *testing.T) {
 	if !ok {
 		t.Errorf("unexpected object type")
 	}
-	if updatedNode.Status.Conditions[0].LastProbeTime.IsZero() {
+	if updatedNode.Status.Conditions[0].LastHeartbeatTime.IsZero() {
 		t.Errorf("unexpected zero last probe timestamp")
 	}
 	if updatedNode.Status.Conditions[0].LastTransitionTime.IsZero() {
 		t.Errorf("unexpected zero last transition timestamp")
 	}
-	updatedNode.Status.Conditions[0].LastProbeTime = util.Time{}
+	updatedNode.Status.Conditions[0].LastHeartbeatTime = util.Time{}
 	updatedNode.Status.Conditions[0].LastTransitionTime = util.Time{}
 	if !reflect.DeepEqual(expectedNode, updatedNode) {
 		t.Errorf("unexpected objects: %s", util.ObjectDiff(expectedNode, updatedNode))
@@ -3138,7 +3138,7 @@ func TestUpdateExistingNodeStatus(t *testing.T) {
 						Type:               api.NodeReady,
 						Status:             api.ConditionTrue,
 						Reason:             fmt.Sprintf("kubelet is posting ready status"),
-						LastProbeTime:      util.Date(2012, 1, 1, 0, 0, 0, 0, time.UTC),
+						LastHeartbeatTime:  util.Date(2012, 1, 1, 0, 0, 0, 0, time.UTC),
 						LastTransitionTime: util.Date(2012, 1, 1, 0, 0, 0, 0, time.UTC),
 					},
 				},
@@ -3173,7 +3173,7 @@ func TestUpdateExistingNodeStatus(t *testing.T) {
 					Type:               api.NodeReady,
 					Status:             api.ConditionTrue,
 					Reason:             fmt.Sprintf("kubelet is posting ready status"),
-					LastProbeTime:      util.Time{}, // placeholder
+					LastHeartbeatTime:  util.Time{}, // placeholder
 					LastTransitionTime: util.Time{}, // placeholder
 				},
 			},
@@ -3205,14 +3205,14 @@ func TestUpdateExistingNodeStatus(t *testing.T) {
 		t.Errorf("unexpected object type")
 	}
 	// Expect LastProbeTime to be updated to Now, while LastTransitionTime to be the same.
-	if reflect.DeepEqual(updatedNode.Status.Conditions[0].LastProbeTime.Rfc3339Copy().UTC(), util.Date(2012, 1, 1, 0, 0, 0, 0, time.UTC).Time) {
+	if reflect.DeepEqual(updatedNode.Status.Conditions[0].LastHeartbeatTime.Rfc3339Copy().UTC(), util.Date(2012, 1, 1, 0, 0, 0, 0, time.UTC).Time) {
 		t.Errorf("expected \n%v\n, got \n%v", util.Now(), util.Date(2012, 1, 1, 0, 0, 0, 0, time.UTC))
 	}
 	if !reflect.DeepEqual(updatedNode.Status.Conditions[0].LastTransitionTime.Rfc3339Copy().UTC(), util.Date(2012, 1, 1, 0, 0, 0, 0, time.UTC).Time) {
 		t.Errorf("expected \n%#v\n, got \n%#v", updatedNode.Status.Conditions[0].LastTransitionTime.Rfc3339Copy(),
 			util.Date(2012, 1, 1, 0, 0, 0, 0, time.UTC))
 	}
-	updatedNode.Status.Conditions[0].LastProbeTime = util.Time{}
+	updatedNode.Status.Conditions[0].LastHeartbeatTime = util.Time{}
 	updatedNode.Status.Conditions[0].LastTransitionTime = util.Time{}
 	if !reflect.DeepEqual(expectedNode, updatedNode) {
 		t.Errorf("expected \n%v\n, got \n%v", expectedNode, updatedNode)