Adding support for identifying nodes that have been deleted from clou…

…d provider that are still registered within Kubernetes. Including code changes first introduced in PR#4211, which will remove taints from all nodes on restarts.

cluster-autoscaler/cloudprovider/test/test_cloud_provider.go

@@ -253,6 +253,14 @@ func (tcp *TestCloudProvider) AddNode(nodeGroupId string, node *apiv1.Node) {
 	tcp.nodes[node.Name] = nodeGroupId
 }
 
+// DeleteNode delete the given node from the provider.
+func (tcp *TestCloudProvider) DeleteNode(node *apiv1.Node) {
+	tcp.Lock()
+	defer tcp.Unlock()
+
+	delete(tcp.nodes, node.Name)
+}
+
 // GetResourceLimiter returns struct containing limits (max, min) for resources (cores, memory etc.).
 func (tcp *TestCloudProvider) GetResourceLimiter() (*cloudprovider.ResourceLimiter, error) {
 	return tcp.resourceLimiter, nil

cluster-autoscaler/clusterstate/clusterstate.go

@@ -28,7 +28,6 @@ import (
 	"k8s.io/autoscaler/cluster-autoscaler/clusterstate/utils"
 	"k8s.io/autoscaler/cluster-autoscaler/metrics"
 	"k8s.io/autoscaler/cluster-autoscaler/utils/backoff"
-	"k8s.io/autoscaler/cluster-autoscaler/utils/deletetaint"
 	kube_util "k8s.io/autoscaler/cluster-autoscaler/utils/kubernetes"
 
 	apiv1 "k8s.io/api/core/v1"
@@ -100,6 +99,15 @@ type UnregisteredNode struct {
 	UnregisteredSince time.Time
 }
 
+// DeletedNode contains information about nodes that have been removed from cluster provider side
+// but are still registered in Kubernetes.
+type DeletedNode struct {
+	// Node instance registered in Kubernetes.
+	Node *apiv1.Node
+	// DeletedSince is the time when the node was detected as deleted.
+	DeletedSince time.Time
+}
+
 // ScaleUpFailure contains information about a failure of a scale-up.
 type ScaleUpFailure struct {
 	NodeGroup cloudprovider.NodeGroup
@@ -121,6 +129,7 @@ type ClusterStateRegistry struct {
 	acceptableRanges                   map[string]AcceptableRange
 	incorrectNodeGroupSizes            map[string]IncorrectNodeGroupSize
 	unregisteredNodes                  map[string]UnregisteredNode
+	deletedNodes                       map[string]DeletedNode
 	candidatesForScaleDown             map[string][]string
 	backoff                            backoff.Backoff
 	lastStatus                         *api.ClusterAutoscalerStatus
@@ -153,6 +162,7 @@ func NewClusterStateRegistry(cloudProvider cloudprovider.CloudProvider, config C
 		acceptableRanges:                make(map[string]AcceptableRange),
 		incorrectNodeGroupSizes:         make(map[string]IncorrectNodeGroupSize),
 		unregisteredNodes:               make(map[string]UnregisteredNode),
+		deletedNodes:                    make(map[string]DeletedNode),
 		candidatesForScaleDown:          make(map[string][]string),
 		backoff:                         backoff,
 		lastStatus:                      emptyStatus,
@@ -296,7 +306,7 @@ func (csr *ClusterStateRegistry) UpdateNodes(nodes []*apiv1.Node, nodeInfosForGr
 		return err
 	}
 	notRegistered := getNotRegisteredNodes(nodes, cloudProviderNodeInstances, currentTime)
-
+	cloudProviderNodesRemoved := getCloudProviderDeletedNodes(nodes, cloudProviderNodeInstances, currentTime)
 	csr.Lock()
 	defer csr.Unlock()
 
@@ -306,6 +316,7 @@ func (csr *ClusterStateRegistry) UpdateNodes(nodes []*apiv1.Node, nodeInfosForGr
 	csr.cloudProviderNodeInstances = cloudProviderNodeInstances
 
 	csr.updateUnregisteredNodes(notRegistered)
+	csr.updateCloudProviderDeletedNodes(cloudProviderNodesRemoved)
 	csr.updateReadinessStats(currentTime)
 
 	// update acceptable ranges based on requests from last loop and targetSizes
@@ -541,7 +552,7 @@ func (csr *ClusterStateRegistry) updateReadinessStats(currentTime time.Time) {
 
 	update := func(current Readiness, node *apiv1.Node, nr kube_util.NodeReadiness) Readiness {
 		current.Registered++
-		if deletetaint.HasToBeDeletedTaint(node) {
+		if _, exists := csr.deletedNodes[node.Name]; exists {
 			current.Deleted++
 		} else if nr.Ready {
 			current.Ready++
@@ -669,6 +680,30 @@ func (csr *ClusterStateRegistry) GetUnregisteredNodes() []UnregisteredNode {
 	return result
 }
 
+func (csr *ClusterStateRegistry) updateCloudProviderDeletedNodes(deletedNodes []DeletedNode) {
+	result := make(map[string]DeletedNode)
+	for _, deleted := range deletedNodes {
+		if prev, found := csr.deletedNodes[deleted.Node.Name]; found {
+			result[deleted.Node.Name] = prev
+		} else {
+			result[deleted.Node.Name] = deleted
+		}
+	}
+	csr.deletedNodes = result
+}
+
+//GetCloudProviderDeletedNodes returns a list of all nodes removed from cloud provider but registered in Kubernetes.
+func (csr *ClusterStateRegistry) GetCloudProviderDeletedNodes() []DeletedNode {
+	csr.Lock()
+	defer csr.Unlock()
+
+	result := make([]DeletedNode, 0, len(csr.deletedNodes))
+	for _, deleted := range csr.deletedNodes {
+		result = append(result, deleted)
+	}
+	return result
+}
+
 // UpdateScaleDownCandidates updates scale down candidates
 func (csr *ClusterStateRegistry) UpdateScaleDownCandidates(nodes []*apiv1.Node, now time.Time) {
 	result := make(map[string][]string)
@@ -958,6 +993,26 @@ func getNotRegisteredNodes(allNodes []*apiv1.Node, cloudProviderNodeInstances ma
 	return notRegistered
 }
 
+// Calculates which of the registered nodes in Kubernetes that do not exist in cloud provider.
+func getCloudProviderDeletedNodes(allNodes []*apiv1.Node, cloudProviderNodeInstances map[string][]cloudprovider.Instance, time time.Time) []DeletedNode {
+	cloudRegistered := sets.NewString()
+	for _, instances := range cloudProviderNodeInstances {
+		for _, instance := range instances {
+			cloudRegistered.Insert(instance.Id)
+		}
+	}
+	nodesRemoved := make([]DeletedNode, 0)
+	for _, node := range allNodes {
+		if !cloudRegistered.Has(node.Spec.ProviderID) {
+			nodesRemoved = append(nodesRemoved, DeletedNode{
+				Node:         node,
+				DeletedSince: time,
+			})
+		}
+	}
+	return nodesRemoved
+}
+
 // GetAutoscaledNodesCount calculates and returns the actual and the target number of nodes
 // belonging to autoscaled node groups in the cluster.
 func (csr *ClusterStateRegistry) GetAutoscaledNodesCount() (currentSize, targetSize int) {

cluster-autoscaler/clusterstate/clusterstate_test.go

@@ -17,6 +17,7 @@ limitations under the License.
 package clusterstate
 
 import (
+	"fmt"
 	"testing"
 	"time"
 
@@ -27,6 +28,7 @@ import (
 	testprovider "k8s.io/autoscaler/cluster-autoscaler/cloudprovider/test"
 	"k8s.io/autoscaler/cluster-autoscaler/clusterstate/api"
 	"k8s.io/autoscaler/cluster-autoscaler/clusterstate/utils"
+	"k8s.io/autoscaler/cluster-autoscaler/utils/deletetaint"
 	. "k8s.io/autoscaler/cluster-autoscaler/utils/test"
 	"k8s.io/client-go/kubernetes/fake"
 	kube_record "k8s.io/client-go/tools/record"
@@ -481,14 +483,30 @@ func TestUpcomingNodes(t *testing.T) {
 	provider.AddNodeGroup("ng4", 1, 10, 1)
 	provider.AddNode("ng4", ng4_1)
 
+	// One node is already there, for a second nde deletion / draining was already started.
+	ng5_1 := BuildTestNode("ng5-1", 1000, 1000)
+	SetNodeReadyState(ng5_1, true, now.Add(-time.Minute))
+	ng5_2 := BuildTestNode("ng5-2", 1000, 1000)
+	SetNodeReadyState(ng5_2, true, now.Add(-time.Minute))
+	ng5_2.Spec.Taints = []apiv1.Taint{
+		{
+			Key:    deletetaint.ToBeDeletedTaint,
+			Value:  fmt.Sprint(time.Now().Unix()),
+			Effect: apiv1.TaintEffectNoSchedule,
+		},
+	}
+	provider.AddNodeGroup("ng5", 1, 10, 2)
+	provider.AddNode("ng5", ng5_1)
+	provider.AddNode("ng5", ng5_2)
+
 	assert.NotNil(t, provider)
 	fakeClient := &fake.Clientset{}
 	fakeLogRecorder, _ := utils.NewStatusMapRecorder(fakeClient, "kube-system", kube_record.NewFakeRecorder(5), false, "my-cool-configmap")
 	clusterstate := NewClusterStateRegistry(provider, ClusterStateRegistryConfig{
 		MaxTotalUnreadyPercentage: 10,
 		OkTotalUnreadyCount:       1,
 	}, fakeLogRecorder, newBackoff())
-	err := clusterstate.UpdateNodes([]*apiv1.Node{ng1_1, ng2_1, ng3_1, ng4_1}, nil, now)
+	err := clusterstate.UpdateNodes([]*apiv1.Node{ng1_1, ng2_1, ng3_1, ng4_1, ng5_1, ng5_2}, nil, now)
 	assert.NoError(t, err)
 	assert.Empty(t, clusterstate.GetScaleUpFailures())
 
@@ -497,6 +515,7 @@ func TestUpcomingNodes(t *testing.T) {
 	assert.Equal(t, 1, upcomingNodes["ng2"])
 	assert.Equal(t, 2, upcomingNodes["ng3"])
 	assert.NotContains(t, upcomingNodes, "ng4")
+	assert.NotContains(t, upcomingNodes, "ng5")
 }
 
 func TestIncorrectSize(t *testing.T) {
@@ -570,6 +589,44 @@ func TestUnregisteredNodes(t *testing.T) {
 	assert.Equal(t, 0, len(clusterstate.GetUnregisteredNodes()))
 }
 
+func TestCloudProviderDeletedNodes(t *testing.T) {
+	ng1_1 := BuildTestNode("ng1-1", 1000, 1000)
+	ng1_1.Spec.ProviderID = "ng1-1"
+	ng1_2 := BuildTestNode("ng1-2", 1000, 1000)
+	ng1_2.Spec.ProviderID = "ng1-2"
+	provider := testprovider.NewTestCloudProvider(nil, nil)
+	provider.AddNodeGroup("ng1", 1, 10, 2)
+	provider.AddNode("ng1", ng1_1)
+	provider.AddNode("ng1", ng1_2)
+
+	fakeClient := &fake.Clientset{}
+	fakeLogRecorder, _ := utils.NewStatusMapRecorder(fakeClient, "kube-system", kube_record.NewFakeRecorder(5), false, "my-cool-configmap")
+	clusterstate := NewClusterStateRegistry(provider, ClusterStateRegistryConfig{
+		MaxTotalUnreadyPercentage: 10,
+		OkTotalUnreadyCount:       1,
+		MaxNodeProvisionTime:      10 * time.Second,
+	}, fakeLogRecorder, newBackoff())
+	err := clusterstate.UpdateNodes([]*apiv1.Node{ng1_1, ng1_2}, nil, time.Now().Add(-time.Minute))
+
+	// Nodes are registered correctly between Kubernetes and cloud provider.
+	assert.NoError(t, err)
+	assert.Equal(t, 0, len(clusterstate.GetCloudProviderDeletedNodes()))
+
+	// The node was removed from Cloud Provider
+	// should be counted as Deleted by cluster state
+	provider.DeleteNode(ng1_2)
+	err = clusterstate.UpdateNodes([]*apiv1.Node{ng1_1, ng1_2}, nil, time.Now().Add(time.Minute))
+	assert.NoError(t, err)
+	assert.Equal(t, 1, len(clusterstate.GetCloudProviderDeletedNodes()))
+	assert.Equal(t, "ng1-2", clusterstate.GetUnregisteredNodes()[0].Node.Name)
+	assert.Equal(t, 1, clusterstate.GetClusterReadiness().Deleted)
+
+	// The node is removed from Kubernetes
+	err = clusterstate.UpdateNodes([]*apiv1.Node{ng1_1}, nil, time.Now().Add(time.Minute))
+	assert.NoError(t, err)
+	assert.Equal(t, 0, len(clusterstate.GetCloudProviderDeletedNodes()))
+}
+
 func TestUpdateLastTransitionTimes(t *testing.T) {
 	now := metav1.Time{Time: time.Now()}
 	later := metav1.Time{Time: now.Time.Add(10 * time.Second)}

cluster-autoscaler/core/static_autoscaler.go

@@ -188,14 +188,14 @@ func (a *StaticAutoscaler) cleanUpIfRequired() {
 	}
 
 	// CA can die at any time. Removing taints that might have been left from the previous run.
-	if readyNodes, err := a.ReadyNodeLister().List(); err != nil {
-		klog.Errorf("Failed to list ready nodes, not cleaning up taints: %v", err)
+	if nodes, err := a.AllNodeLister().List(); err != nil {
+		klog.Errorf("Failed to list nodes, not cleaning up taints: %v", err)
 	} else {
-		deletetaint.CleanAllToBeDeleted(readyNodes,
+		deletetaint.CleanAllToBeDeleted(nodes,
 			a.AutoscalingContext.ClientSet, a.Recorder, a.CordonNodeBeforeTerminate)
 		if a.AutoscalingContext.AutoscalingOptions.MaxBulkSoftTaintCount == 0 {
 			// Clean old taints if soft taints handling is disabled
-			deletetaint.CleanAllDeletionCandidates(readyNodes,
+			deletetaint.CleanAllDeletionCandidates(nodes,
 				a.AutoscalingContext.ClientSet, a.Recorder)
 		}
 	}