Merge pull request #13182 from mikedanese/daemon_manager

Add daemon controller

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

@@ -35,6 +35,7 @@ import (
 	"k8s.io/kubernetes/pkg/client/unversioned/clientcmd"
 	clientcmdapi "k8s.io/kubernetes/pkg/client/unversioned/clientcmd/api"
 	"k8s.io/kubernetes/pkg/cloudprovider"
+	"k8s.io/kubernetes/pkg/controller/daemon"
 	"k8s.io/kubernetes/pkg/controller/endpoint"
 	"k8s.io/kubernetes/pkg/controller/namespace"
 	"k8s.io/kubernetes/pkg/controller/node"
@@ -63,6 +64,7 @@ type CMServer struct {
 	CloudConfigFile                   string
 	ConcurrentEndpointSyncs           int
 	ConcurrentRCSyncs                 int
+	ConcurrentDSCSyncs                int
 	ServiceSyncPeriod                 time.Duration
 	NodeSyncPeriod                    time.Duration
 	ResourceQuotaSyncPeriod           time.Duration
@@ -98,6 +100,7 @@ func NewCMServer() *CMServer {
 		Address:                           net.ParseIP("127.0.0.1"),
 		ConcurrentEndpointSyncs:           5,
 		ConcurrentRCSyncs:                 5,
+		ConcurrentDSCSyncs:                2,
 		ServiceSyncPeriod:                 5 * time.Minute,
 		NodeSyncPeriod:                    10 * time.Second,
 		ResourceQuotaSyncPeriod:           10 * time.Second,
@@ -213,6 +216,9 @@ func (s *CMServer) Run(_ []string) error {
 	controllerManager := replicationControllerPkg.NewReplicationManager(kubeClient, replicationControllerPkg.BurstReplicas)
 	go controllerManager.Run(s.ConcurrentRCSyncs, util.NeverStop)
 
+	go daemon.NewDaemonSetsController(kubeClient).
+		Run(s.ConcurrentDSCSyncs, util.NeverStop)
+
 	cloud, err := cloudprovider.InitCloudProvider(s.CloudProvider, s.CloudConfigFile)
 	if err != nil {
 		glog.Fatalf("Cloud provider could not be initialized: %v", err)

contrib/mesos/pkg/controllermanager/controllermanager.go

@@ -47,6 +47,7 @@ import (
 	"github.com/golang/glog"
 	"github.com/prometheus/client_golang/prometheus"
 	"github.com/spf13/pflag"
+	"k8s.io/kubernetes/pkg/controller/daemon"
 )
 
 // CMServer is the main context object for the controller manager.
@@ -113,6 +114,9 @@ func (s *CMServer) Run(_ []string) error {
 	controllerManager := replicationcontroller.NewReplicationManager(kubeClient, replicationcontroller.BurstReplicas)
 	go controllerManager.Run(s.ConcurrentRCSyncs, util.NeverStop)
 
+	go daemon.NewDaemonSetsController(kubeClient).
+		Run(s.ConcurrentDSCSyncs, util.NeverStop)
+
 	//TODO(jdef) should eventually support more cloud providers here
 	if s.CloudProvider != mesos.ProviderName {
 		glog.Fatalf("Only provider %v is supported, you specified %v", mesos.ProviderName, s.CloudProvider)

pkg/controller/controller_utils.go

@@ -20,17 +20,19 @@ import (
 	"fmt"
 	"time"
 
+	"sync/atomic"
+
 	"github.com/golang/glog"
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/api/latest"
 	"k8s.io/kubernetes/pkg/api/validation"
+	"k8s.io/kubernetes/pkg/apis/experimental"
 	"k8s.io/kubernetes/pkg/client/cache"
 	"k8s.io/kubernetes/pkg/client/record"
 	client "k8s.io/kubernetes/pkg/client/unversioned"
 	"k8s.io/kubernetes/pkg/controller/framework"
 	"k8s.io/kubernetes/pkg/labels"
 	"k8s.io/kubernetes/pkg/runtime"
-	"sync/atomic"
 )
 
 const (
@@ -213,6 +215,8 @@ func NewControllerExpectations() *ControllerExpectations {
 type PodControlInterface interface {
 	// CreateReplica creates new replicated pods according to the spec.
 	CreateReplica(namespace string, controller *api.ReplicationController) error
+	// CreateReplicaOnNode creates a new pod according to the spec on the specified node.
+	CreateReplicaOnNode(namespace string, ds *experimental.DaemonSet, nodeName string) error
 	// DeletePod deletes the pod identified by podID.
 	DeletePod(namespace string, podID string) error
 }
@@ -290,6 +294,40 @@ func (r RealPodControl) CreateReplica(namespace string, controller *api.Replicat
 	return nil
 }
 
+func (r RealPodControl) CreateReplicaOnNode(namespace string, ds *experimental.DaemonSet, nodeName string) error {
+	desiredLabels := getReplicaLabelSet(ds.Spec.Template)
+	desiredAnnotations, err := getReplicaAnnotationSet(ds.Spec.Template, ds)
+	if err != nil {
+		return err
+	}
+	prefix := getReplicaPrefix(ds.Name)
+
+	pod := &api.Pod{
+		ObjectMeta: api.ObjectMeta{
+			Labels:       desiredLabels,
+			Annotations:  desiredAnnotations,
+			GenerateName: prefix,
+		},
+	}
+	if err := api.Scheme.Convert(&ds.Spec.Template.Spec, &pod.Spec); err != nil {
+		return fmt.Errorf("unable to convert pod template: %v", err)
+	}
+	// if a pod does not have labels then it cannot be controlled by any controller
+	if labels.Set(pod.Labels).AsSelector().Empty() {
+		return fmt.Errorf("unable to create pod replica, no labels")
+	}
+	pod.Spec.NodeName = nodeName
+	if newPod, err := r.KubeClient.Pods(namespace).Create(pod); err != nil {
+		r.Recorder.Eventf(ds, "failedCreate", "Error creating: %v", err)
+		return fmt.Errorf("unable to create pod replica: %v", err)
+	} else {
+		glog.V(4).Infof("Controller %v created pod %v", ds.Name, newPod.Name)
+		r.Recorder.Eventf(ds, "successfulCreate", "Created pod: %v", newPod.Name)
+	}
+
+	return nil
+}
+
 func (r RealPodControl) DeletePod(namespace, podID string) error {
 	return r.KubeClient.Pods(namespace).Delete(podID, nil)
 }

pkg/controller/daemon/controller.go

@@ -0,0 +1,497 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package daemon
+
+import (
+	"reflect"
+	"sort"
+	"time"
+
+	"github.com/golang/glog"
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/apis/experimental"
+	"k8s.io/kubernetes/pkg/client/cache"
+	"k8s.io/kubernetes/pkg/client/record"
+	client "k8s.io/kubernetes/pkg/client/unversioned"
+	"k8s.io/kubernetes/pkg/controller"
+	"k8s.io/kubernetes/pkg/controller/framework"
+	"k8s.io/kubernetes/pkg/fields"
+	"k8s.io/kubernetes/pkg/labels"
+	"k8s.io/kubernetes/pkg/runtime"
+	"k8s.io/kubernetes/pkg/util"
+	"k8s.io/kubernetes/pkg/util/workqueue"
+	"k8s.io/kubernetes/pkg/watch"
+)
+
+const (
+	// Daemon sets will periodically check that their daemon pods are running as expected.
+	FullDaemonSetResyncPeriod = 30 * time.Second // TODO: Figure out if this time seems reasonable.
+	// Nodes don't need relisting.
+	FullNodeResyncPeriod = 0
+	// Daemon pods don't need relisting.
+	FullDaemonPodResyncPeriod = 0
+	// If sending a status upate to API server fails, we retry a finite number of times.
+	StatusUpdateRetries = 1
+)
+
+// DaemonSetsController is responsible for synchronizing DaemonSet objects stored
+// in the system with actual running pods.
+type DaemonSetsController struct {
+	kubeClient client.Interface
+	podControl controller.PodControlInterface
+
+	// To allow injection of syncDaemonSet for testing.
+	syncHandler func(dsKey string) error
+	// A TTLCache of pod creates/deletes each ds expects to see
+	expectations controller.ControllerExpectationsInterface
+	// A store of daemon sets
+	dsStore cache.StoreToDaemonSetLister
+	// A store of pods
+	podStore cache.StoreToPodLister
+	// A store of nodes
+	nodeStore cache.StoreToNodeLister
+	// Watches changes to all daemon sets.
+	dsController *framework.Controller
+	// Watches changes to all pods
+	podController *framework.Controller
+	// Watches changes to all nodes.
+	nodeController *framework.Controller
+	// Daemon sets that need to be synced.
+	queue *workqueue.Type
+}
+
+func NewDaemonSetsController(kubeClient client.Interface) *DaemonSetsController {
+	eventBroadcaster := record.NewBroadcaster()
+	eventBroadcaster.StartLogging(glog.Infof)
+	eventBroadcaster.StartRecordingToSink(kubeClient.Events(""))
+
+	dsc := &DaemonSetsController{
+		kubeClient: kubeClient,
+		podControl: controller.RealPodControl{
+			KubeClient: kubeClient,
+			Recorder:   eventBroadcaster.NewRecorder(api.EventSource{Component: "daemon-set"}),
+		},
+		expectations: controller.NewControllerExpectations(),
+		queue:        workqueue.New(),
+	}
+	// Manage addition/update of daemon sets.
+	dsc.dsStore.Store, dsc.dsController = framework.NewInformer(
+		&cache.ListWatch{
+			ListFunc: func() (runtime.Object, error) {
+				return dsc.kubeClient.Experimental().DaemonSets(api.NamespaceAll).List(labels.Everything())
+			},
+			WatchFunc: func(rv string) (watch.Interface, error) {
+				return dsc.kubeClient.Experimental().DaemonSets(api.NamespaceAll).Watch(labels.Everything(), fields.Everything(), rv)
+			},
+		},
+		&experimental.DaemonSet{},
+		FullDaemonSetResyncPeriod,
+		framework.ResourceEventHandlerFuncs{
+			AddFunc: func(obj interface{}) {
+				ds := obj.(*experimental.DaemonSet)
+				glog.V(4).Infof("Adding daemon set %s", ds.Name)
+				dsc.enqueueDaemonSet(obj)
+			},
+			UpdateFunc: func(old, cur interface{}) {
+				oldDS := old.(*experimental.DaemonSet)
+				glog.V(4).Infof("Updating daemon set %s", oldDS.Name)
+				dsc.enqueueDaemonSet(cur)
+			},
+			DeleteFunc: func(obj interface{}) {
+				ds := obj.(*experimental.DaemonSet)
+				glog.V(4).Infof("Deleting daemon set %s", ds.Name)
+				dsc.enqueueDaemonSet(obj)
+			},
+		},
+	)
+	// Watch for creation/deletion of pods. The reason we watch is that we don't want a daemon set to create/delete
+	// more pods until all the effects (expectations) of a daemon set's create/delete have been observed.
+	dsc.podStore.Store, dsc.podController = framework.NewInformer(
+		&cache.ListWatch{
+			ListFunc: func() (runtime.Object, error) {
+				return dsc.kubeClient.Pods(api.NamespaceAll).List(labels.Everything(), fields.Everything())
+			},
+			WatchFunc: func(rv string) (watch.Interface, error) {
+				return dsc.kubeClient.Pods(api.NamespaceAll).Watch(labels.Everything(), fields.Everything(), rv)
+			},
+		},
+		&api.Pod{},
+		FullDaemonPodResyncPeriod,
+		framework.ResourceEventHandlerFuncs{
+			AddFunc:    dsc.addPod,
+			UpdateFunc: dsc.updatePod,
+			DeleteFunc: dsc.deletePod,
+		},
+	)
+	// Watch for new nodes or updates to nodes - daemon pods are launched on new nodes, and possibly when labels on nodes change,
+	dsc.nodeStore.Store, dsc.nodeController = framework.NewInformer(
+		&cache.ListWatch{
+			ListFunc: func() (runtime.Object, error) {
+				return dsc.kubeClient.Nodes().List(labels.Everything(), fields.Everything())
+			},
+			WatchFunc: func(rv string) (watch.Interface, error) {
+				return dsc.kubeClient.Nodes().Watch(labels.Everything(), fields.Everything(), rv)
+			},
+		},
+		&api.Node{},
+		FullNodeResyncPeriod,
+		framework.ResourceEventHandlerFuncs{
+			AddFunc:    dsc.addNode,
+			UpdateFunc: dsc.updateNode,
+		},
+	)
+	dsc.syncHandler = dsc.syncDaemonSet
+	return dsc
+}
+
+// Run begins watching and syncing daemon sets.
+func (dsc *DaemonSetsController) Run(workers int, stopCh <-chan struct{}) {
+	go dsc.dsController.Run(stopCh)
+	go dsc.podController.Run(stopCh)
+	go dsc.nodeController.Run(stopCh)
+	for i := 0; i < workers; i++ {
+		go util.Until(dsc.worker, time.Second, stopCh)
+	}
+	<-stopCh
+	glog.Infof("Shutting down Daemon Set Controller")
+	dsc.queue.ShutDown()
+}
+
+func (dsc *DaemonSetsController) worker() {
+	for {
+		func() {
+			dsKey, quit := dsc.queue.Get()
+			if quit {
+				return
+			}
+			defer dsc.queue.Done(dsKey)
+			err := dsc.syncHandler(dsKey.(string))
+			if err != nil {
+				glog.Errorf("Error syncing daemon set with key %s: %v", dsKey.(string), err)
+			}
+		}()
+	}
+}
+
+func (dsc *DaemonSetsController) enqueueAllDaemonSets() {
+	glog.V(4).Infof("Enqueueing all daemon sets")
+	ds, err := dsc.dsStore.List()
+	if err != nil {
+		glog.Errorf("Error enqueueing daemon sets: %v", err)
+		return
+	}
+	for i := range ds {
+		dsc.enqueueDaemonSet(&ds[i])
+	}
+}
+
+func (dsc *DaemonSetsController) enqueueDaemonSet(obj interface{}) {
+	key, err := controller.KeyFunc(obj)
+	if err != nil {
+		glog.Errorf("Couldn't get key for object %+v: %v", obj, err)
+		return
+	}
+	dsc.queue.Add(key)
+}
+
+func (dsc *DaemonSetsController) getPodDaemonSet(pod *api.Pod) *experimental.DaemonSet {
+	sets, err := dsc.dsStore.GetPodDaemonSets(pod)
+	if err != nil {
+		glog.V(4).Infof("No daemon sets found for pod %v, daemon set controller will avoid syncing", pod.Name)
+		return nil
+	}
+	// More than two items in this list indicates user error. If two daemon
+	// sets overlap, sort by creation timestamp, subsort by name, then pick
+	// the first.
+	glog.Errorf("user error! more than one daemon is selecting pods with labels: %+v", pod.Labels)
+	sort.Sort(byCreationTimestamp(sets))
+	return &sets[0]
+}
+
+func (dsc *DaemonSetsController) addPod(obj interface{}) {
+	pod := obj.(*api.Pod)
+	glog.V(4).Infof("Pod %s added.", pod.Name)
+	if ds := dsc.getPodDaemonSet(pod); ds != nil {
+		dsKey, err := controller.KeyFunc(ds)
+		if err != nil {
+			glog.Errorf("Couldn't get key for object %+v: %v", ds, err)
+			return
+		}
+		dsc.expectations.CreationObserved(dsKey)
+		dsc.enqueueDaemonSet(ds)
+	}
+}
+
+// When a pod is updated, figure out what sets manage it and wake them
+// up. If the labels of the pod have changed we need to awaken both the old
+// and new set. old and cur must be *api.Pod types.
+func (dsc *DaemonSetsController) updatePod(old, cur interface{}) {
+	if api.Semantic.DeepEqual(old, cur) {
+		// A periodic relist will send update events for all known pods.
+		return
+	}
+	curPod := cur.(*api.Pod)
+	glog.V(4).Infof("Pod %s updated.", curPod.Name)
+	if curDS := dsc.getPodDaemonSet(curPod); curDS != nil {
+		dsc.enqueueDaemonSet(curDS)
+	}
+	oldPod := old.(*api.Pod)
+	// If the labels have not changed, then the daemon set responsible for
+	// the pod is the same as it was before. In that case we have enqueued the daemon
+	// set above, and do not have to enqueue the set again.
+	if !reflect.DeepEqual(curPod.Labels, oldPod.Labels) {
+		// It's ok if both oldDS and curDS are the same, because curDS will set
+		// the expectations on its run so oldDS will have no effect.
+		if oldDS := dsc.getPodDaemonSet(oldPod); oldDS != nil {
+			dsc.enqueueDaemonSet(oldDS)
+		}
+	}
+}
+
+func (dsc *DaemonSetsController) deletePod(obj interface{}) {
+	pod, ok := obj.(*api.Pod)
+	glog.V(4).Infof("Pod %s deleted.", pod.Name)
+	// When a delete is dropped, the relist will notice a pod in the store not
+	// in the list, leading to the insertion of a tombstone object which contains
+	// the deleted key/value. Note that this value might be stale. If the pod
+	// changed labels the new rc will not be woken up till the periodic resync.
+	if !ok {
+		tombstone, ok := obj.(cache.DeletedFinalStateUnknown)
+		if !ok {
+			glog.Errorf("Couldn't get object from tombstone %+v", obj)
+			return
+		}
+		pod, ok = tombstone.Obj.(*api.Pod)
+		if !ok {
+			glog.Errorf("Tombstone contained object that is not a pod %+v", obj)
+			return
+		}
+	}
+	if ds := dsc.getPodDaemonSet(pod); ds != nil {
+		dsKey, err := controller.KeyFunc(ds)
+		if err != nil {
+			glog.Errorf("Couldn't get key for object %+v: %v", ds, err)
+			return
+		}
+		dsc.expectations.DeletionObserved(dsKey)
+		dsc.enqueueDaemonSet(ds)
+	}
+}
+
+func (dsc *DaemonSetsController) addNode(obj interface{}) {
+	// TODO: it'd be nice to pass a hint with these enqueues, so that each ds would only examine the added node (unless it has other work to do, too).
+	dsc.enqueueAllDaemonSets()
+}
+
+func (dsc *DaemonSetsController) updateNode(old, cur interface{}) {
+	oldNode := old.(*api.Node)
+	curNode := cur.(*api.Node)
+	if api.Semantic.DeepEqual(oldNode.Name, curNode.Name) && api.Semantic.DeepEqual(oldNode.Namespace, curNode.Namespace) && api.Semantic.DeepEqual(oldNode.Labels, curNode.Labels) {
+		// A periodic relist will send update events for all known pods.
+		return
+	}
+	// TODO: it'd be nice to pass a hint with these enqueues, so that each ds would only examine the added node (unless it has other work to do, too).
+	dsc.enqueueAllDaemonSets()
+}
+
+// getNodesToDaemonSetPods returns a map from nodes to daemon pods (corresponding to ds) running on the nodes.
+func (dsc *DaemonSetsController) getNodesToDaemonPods(ds *experimental.DaemonSet) (map[string][]*api.Pod, error) {
+	nodeToDaemonPods := make(map[string][]*api.Pod)
+	daemonPods, err := dsc.podStore.Pods(ds.Namespace).List(labels.Set(ds.Spec.Selector).AsSelector())
+	if err != nil {
+		return nodeToDaemonPods, err
+	}
+	for i := range daemonPods.Items {
+		nodeName := daemonPods.Items[i].Spec.NodeName
+		nodeToDaemonPods[nodeName] = append(nodeToDaemonPods[nodeName], &daemonPods.Items[i])
+	}
+	return nodeToDaemonPods, nil
+}
+
+func (dsc *DaemonSetsController) manage(ds *experimental.DaemonSet) {
+	// Find out which nodes are running the daemon pods selected by ds.
+	nodeToDaemonPods, err := dsc.getNodesToDaemonPods(ds)
+	if err != nil {
+		glog.Errorf("Error getting node to daemon pod mapping for daemon set %+v: %v", ds, err)
+	}
+
+	// For each node, if the node is running the daemon pod but isn't supposed to, kill the daemon
+	// pod. If the node is supposed to run the daemon pod, but isn't, create the daemon pod on the node.
+	nodeList, err := dsc.nodeStore.List()
+	if err != nil {
+		glog.Errorf("Couldn't get list of nodes when syncing daemon set %+v: %v", ds, err)
+	}
+	var nodesNeedingDaemonPods, podsToDelete []string
+	for i := range nodeList.Items {
+		// Check if the node satisfies the daemon set's node selector.
+		nodeSelector := labels.Set(ds.Spec.Template.Spec.NodeSelector).AsSelector()
+		shouldRun := nodeSelector.Matches(labels.Set(nodeList.Items[i].Labels))
+		// If the daemon set specifies a node name, check that it matches with nodeName.
+		nodeName := nodeList.Items[i].Name
+		shouldRun = shouldRun && (ds.Spec.Template.Spec.NodeName == "" || ds.Spec.Template.Spec.NodeName == nodeName)
+		daemonPods, isRunning := nodeToDaemonPods[nodeName]
+		if shouldRun && !isRunning {
+			// If daemon pod is supposed to be running on node, but isn't, create daemon pod.
+			nodesNeedingDaemonPods = append(nodesNeedingDaemonPods, nodeName)
+		} else if shouldRun && len(daemonPods) > 1 {
+			// If daemon pod is supposed to be running on node, but more than 1 daemon pod is running, delete the excess daemon pods.
+			// TODO: sort the daemon pods by creation time, so the the oldest is preserved.
+			for i := 1; i < len(daemonPods); i++ {
+				podsToDelete = append(podsToDelete, daemonPods[i].Name)
+			}
+		} else if !shouldRun && isRunning {
+			// If daemon pod isn't supposed to run on node, but it is, delete all daemon pods on node.
+			for i := range daemonPods {
+				podsToDelete = append(podsToDelete, daemonPods[i].Name)
+			}
+		}
+	}
+
+	// We need to set expectations before creating/deleting pods to avoid race conditions.
+	dsKey, err := controller.KeyFunc(ds)
+	if err != nil {
+		glog.Errorf("Couldn't get key for object %+v: %v", ds, err)
+		return
+	}
+	dsc.expectations.SetExpectations(dsKey, len(nodesNeedingDaemonPods), len(podsToDelete))
+
+	glog.V(4).Infof("Nodes needing daemon pods for daemon set %s: %+v", ds.Name, nodesNeedingDaemonPods)
+	for i := range nodesNeedingDaemonPods {
+		if err := dsc.podControl.CreateReplicaOnNode(ds.Namespace, ds, nodesNeedingDaemonPods[i]); err != nil {
+			glog.V(2).Infof("Failed creation, decrementing expectations for set %q/%q", ds.Namespace, ds.Name)
+			dsc.expectations.CreationObserved(dsKey)
+			util.HandleError(err)
+		}
+	}
+
+	glog.V(4).Infof("Pods to delete for daemon set %s: %+v", ds.Name, podsToDelete)
+	for i := range podsToDelete {
+		if err := dsc.podControl.DeletePod(ds.Namespace, podsToDelete[i]); err != nil {
+			glog.V(2).Infof("Failed deletion, decrementing expectations for set %q/%q", ds.Namespace, ds.Name)
+			dsc.expectations.DeletionObserved(dsKey)
+			util.HandleError(err)
+		}
+	}
+}
+
+func storeDaemonSetStatus(dsClient client.DaemonSetInterface, ds *experimental.DaemonSet, desiredNumberScheduled, currentNumberScheduled, numberMisscheduled int) error {
+	if ds.Status.DesiredNumberScheduled == desiredNumberScheduled && ds.Status.CurrentNumberScheduled == currentNumberScheduled && ds.Status.NumberMisscheduled == numberMisscheduled {
+		return nil
+	}
+
+	var updateErr, getErr error
+	for i := 0; i <= StatusUpdateRetries; i++ {
+		ds.Status.DesiredNumberScheduled = desiredNumberScheduled
+		ds.Status.CurrentNumberScheduled = currentNumberScheduled
+		ds.Status.NumberMisscheduled = numberMisscheduled
+		_, updateErr = dsClient.Update(ds)
+		if updateErr == nil {
+			// successful update
+			return nil
+		}
+		// Update the set with the latest resource version for the next poll
+		if ds, getErr = dsClient.Get(ds.Name); getErr != nil {
+			// If the GET fails we can't trust status.Replicas anymore. This error
+			// is bound to be more interesting than the update failure.
+			return getErr
+		}
+	}
+	return updateErr
+}
+
+func (dsc *DaemonSetsController) updateDaemonSetStatus(ds *experimental.DaemonSet) {
+	glog.Infof("Updating daemon set status")
+	nodeToDaemonPods, err := dsc.getNodesToDaemonPods(ds)
+	if err != nil {
+		glog.Errorf("Error getting node to daemon pod mapping for daemon set %+v: %v", ds, err)
+	}
+
+	nodeList, err := dsc.nodeStore.List()
+	if err != nil {
+		glog.Errorf("Couldn't get list of nodes when updating daemon set %+v: %v", ds, err)
+	}
+
+	var desiredNumberScheduled, currentNumberScheduled, numberMisscheduled int
+	for _, node := range nodeList.Items {
+		nodeSelector := labels.Set(ds.Spec.Template.Spec.NodeSelector).AsSelector()
+		shouldRun := nodeSelector.Matches(labels.Set(node.Labels))
+		numDaemonPods := len(nodeToDaemonPods[node.Name])
+
+		if numDaemonPods > 0 {
+			currentNumberScheduled++
+		}
+
+		if shouldRun {
+			desiredNumberScheduled++
+		} else if numDaemonPods >= 0 {
+			numberMisscheduled++
+		}
+	}
+
+	err = storeDaemonSetStatus(dsc.kubeClient.Experimental().DaemonSets(ds.Namespace), ds, desiredNumberScheduled, currentNumberScheduled, numberMisscheduled)
+	if err != nil {
+		glog.Errorf("Error storing status for daemon set %+v: %v", ds, err)
+	}
+}
+
+func (dsc *DaemonSetsController) syncDaemonSet(key string) error {
+	startTime := time.Now()
+	defer func() {
+		glog.V(4).Infof("Finished syncing daemon set %q (%v)", key, time.Now().Sub(startTime))
+	}()
+	obj, exists, err := dsc.dsStore.Store.GetByKey(key)
+	if err != nil {
+		glog.Infof("Unable to retrieve ds %v from store: %v", key, err)
+		dsc.queue.Add(key)
+		return err
+	}
+	if !exists {
+		glog.V(3).Infof("daemon set has been deleted %v", key)
+		dsc.expectations.DeleteExpectations(key)
+		return nil
+	}
+	ds := obj.(*experimental.DaemonSet)
+
+	// Don't process a daemon set until all its creations and deletions have been processed.
+	// For example if daemon set foo asked for 3 new daemon pods in the previous call to manage,
+	// then we do not want to call manage on foo until the daemon pods have been created.
+	dsKey, err := controller.KeyFunc(ds)
+	if err != nil {
+		glog.Errorf("Couldn't get key for object %+v: %v", ds, err)
+		return err
+	}
+	dsNeedsSync := dsc.expectations.SatisfiedExpectations(dsKey)
+	if dsNeedsSync {
+		dsc.manage(ds)
+	}
+
+	dsc.updateDaemonSetStatus(ds)
+	return nil
+}
+
+// byCreationTimestamp sorts a list by creation timestamp, using their names as a tie breaker.
+type byCreationTimestamp []experimental.DaemonSet
+
+func (o byCreationTimestamp) Len() int      { return len(o) }
+func (o byCreationTimestamp) Swap(i, j int) { o[i], o[j] = o[j], o[i] }
+
+func (o byCreationTimestamp) Less(i, j int) bool {
+	if o[i].CreationTimestamp.Equal(o[j].CreationTimestamp) {
+		return o[i].Name < o[j].Name
+	}
+	return o[i].CreationTimestamp.Before(o[j].CreationTimestamp)
+}

pkg/controller/daemon/controller_test.go

@@ -0,0 +1,321 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package daemon
+
+import (
+	"fmt"
+	"sync"
+	"testing"
+
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/api/testapi"
+	"k8s.io/kubernetes/pkg/apis/experimental"
+	"k8s.io/kubernetes/pkg/client/cache"
+	client "k8s.io/kubernetes/pkg/client/unversioned"
+	"k8s.io/kubernetes/pkg/controller"
+	"k8s.io/kubernetes/pkg/securitycontext"
+)
+
+var (
+	simpleDaemonSetLabel  = map[string]string{"name": "simple-daemon", "type": "production"}
+	simpleDaemonSetLabel2 = map[string]string{"name": "simple-daemon", "type": "test"}
+	simpleNodeLabel       = map[string]string{"color": "blue", "speed": "fast"}
+	simpleNodeLabel2      = map[string]string{"color": "red", "speed": "fast"}
+)
+
+type FakePodControl struct {
+	daemonSet     []experimental.DaemonSet
+	deletePodName []string
+	lock          sync.Mutex
+	err           error
+}
+
+func init() {
+	api.ForTesting_ReferencesAllowBlankSelfLinks = true
+}
+
+func (f *FakePodControl) CreateReplica(namespace string, spec *api.ReplicationController) error {
+	return nil
+}
+
+func (f *FakePodControl) CreateReplicaOnNode(namespace string, ds *experimental.DaemonSet, nodeName string) error {
+	f.lock.Lock()
+	defer f.lock.Unlock()
+	if f.err != nil {
+		return f.err
+	}
+	f.daemonSet = append(f.daemonSet, *ds)
+	return nil
+}
+
+func (f *FakePodControl) DeletePod(namespace string, podName string) error {
+	f.lock.Lock()
+	defer f.lock.Unlock()
+	if f.err != nil {
+		return f.err
+	}
+	f.deletePodName = append(f.deletePodName, podName)
+	return nil
+}
+func (f *FakePodControl) clear() {
+	f.lock.Lock()
+	defer f.lock.Unlock()
+	f.deletePodName = []string{}
+	f.daemonSet = []experimental.DaemonSet{}
+}
+
+func newDaemonSet(name string) *experimental.DaemonSet {
+	return &experimental.DaemonSet{
+		TypeMeta: api.TypeMeta{APIVersion: testapi.Experimental.Version()},
+		ObjectMeta: api.ObjectMeta{
+			Name:      name,
+			Namespace: api.NamespaceDefault,
+		},
+		Spec: experimental.DaemonSetSpec{
+			Selector: simpleDaemonSetLabel,
+			Template: &api.PodTemplateSpec{
+				ObjectMeta: api.ObjectMeta{
+					Labels: simpleDaemonSetLabel,
+				},
+				Spec: api.PodSpec{
+					Containers: []api.Container{
+						{
+							Image: "foo/bar",
+							TerminationMessagePath: api.TerminationMessagePathDefault,
+							ImagePullPolicy:        api.PullIfNotPresent,
+							SecurityContext:        securitycontext.ValidSecurityContextWithContainerDefaults(),
+						},
+					},
+					DNSPolicy: api.DNSDefault,
+				},
+			},
+		},
+	}
+}
+
+func newNode(name string, label map[string]string) *api.Node {
+	return &api.Node{
+		TypeMeta: api.TypeMeta{APIVersion: testapi.Default.Version()},
+		ObjectMeta: api.ObjectMeta{
+			Name:      name,
+			Labels:    label,
+			Namespace: api.NamespaceDefault,
+		},
+	}
+}
+
+func addNodes(nodeStore cache.Store, startIndex, numNodes int, label map[string]string) {
+	for i := startIndex; i < startIndex+numNodes; i++ {
+		nodeStore.Add(newNode(fmt.Sprintf("node-%d", i), label))
+	}
+}
+
+func newPod(podName string, nodeName string, label map[string]string) *api.Pod {
+	pod := &api.Pod{
+		TypeMeta: api.TypeMeta{APIVersion: testapi.Default.Version()},
+		ObjectMeta: api.ObjectMeta{
+			GenerateName: podName,
+			Labels:       label,
+			Namespace:    api.NamespaceDefault,
+		},
+		Spec: api.PodSpec{
+			NodeName: nodeName,
+			Containers: []api.Container{
+				{
+					Image: "foo/bar",
+					TerminationMessagePath: api.TerminationMessagePathDefault,
+					ImagePullPolicy:        api.PullIfNotPresent,
+					SecurityContext:        securitycontext.ValidSecurityContextWithContainerDefaults(),
+				},
+			},
+			DNSPolicy: api.DNSDefault,
+		},
+	}
+	api.GenerateName(api.SimpleNameGenerator, &pod.ObjectMeta)
+	return pod
+}
+
+func addPods(podStore cache.Store, nodeName string, label map[string]string, number int) {
+	for i := 0; i < number; i++ {
+		podStore.Add(newPod(fmt.Sprintf("%s-", nodeName), nodeName, label))
+	}
+}
+
+func newTestController() (*DaemonSetsController, *FakePodControl) {
+	client := client.NewOrDie(&client.Config{Host: "", Version: testapi.Experimental.Version()})
+	manager := NewDaemonSetsController(client)
+	podControl := &FakePodControl{}
+	manager.podControl = podControl
+	return manager, podControl
+}
+
+func validateSyncDaemonSets(t *testing.T, fakePodControl *FakePodControl, expectedCreates, expectedDeletes int) {
+	if len(fakePodControl.daemonSet) != expectedCreates {
+		t.Errorf("Unexpected number of creates.  Expected %d, saw %d\n", expectedCreates, len(fakePodControl.daemonSet))
+	}
+	if len(fakePodControl.deletePodName) != expectedDeletes {
+		t.Errorf("Unexpected number of deletes.  Expected %d, saw %d\n", expectedDeletes, len(fakePodControl.deletePodName))
+	}
+}
+
+func syncAndValidateDaemonSets(t *testing.T, manager *DaemonSetsController, ds *experimental.DaemonSet, podControl *FakePodControl, expectedCreates, expectedDeletes int) {
+	key, err := controller.KeyFunc(ds)
+	if err != nil {
+		t.Errorf("Could not get key for daemon.")
+	}
+	manager.syncHandler(key)
+	validateSyncDaemonSets(t, podControl, expectedCreates, expectedDeletes)
+}
+
+// DaemonSets without node selectors should launch pods on every node.
+func TestSimpleDaemonSetLaunchesPods(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 5, nil)
+	ds := newDaemonSet("foo")
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 5, 0)
+}
+
+// DaemonSets without node selectors should launch pods on every node.
+func TestNoNodesDoesNothing(t *testing.T) {
+	manager, podControl := newTestController()
+	ds := newDaemonSet("foo")
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 0, 0)
+}
+
+// DaemonSets without node selectors should launch pods on every node.
+func TestOneNodeDaemonLaunchesPod(t *testing.T) {
+	manager, podControl := newTestController()
+	manager.nodeStore.Add(newNode("only-node", nil))
+	ds := newDaemonSet("foo")
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 1, 0)
+}
+
+// Controller should not create pods on nodes which have daemon pods, and should remove excess pods from nodes that have extra pods.
+func TestDealsWithExistingPods(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 5, nil)
+	addPods(manager.podStore.Store, "node-1", simpleDaemonSetLabel, 1)
+	addPods(manager.podStore.Store, "node-2", simpleDaemonSetLabel, 2)
+	addPods(manager.podStore.Store, "node-3", simpleDaemonSetLabel, 5)
+	addPods(manager.podStore.Store, "node-4", simpleDaemonSetLabel2, 2)
+	ds := newDaemonSet("foo")
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 2, 5)
+}
+
+// Daemon with node selector should launch pods on nodes matching selector.
+func TestSelectorDaemonLaunchesPods(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 4, nil)
+	addNodes(manager.nodeStore.Store, 4, 3, simpleNodeLabel)
+	daemon := newDaemonSet("foo")
+	daemon.Spec.Template.Spec.NodeSelector = simpleNodeLabel
+	manager.dsStore.Add(daemon)
+	syncAndValidateDaemonSets(t, manager, daemon, podControl, 3, 0)
+}
+
+// Daemon with node selector should delete pods from nodes that do not satisfy selector.
+func TestSelectorDaemonDeletesUnselectedPods(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 5, nil)
+	addNodes(manager.nodeStore.Store, 5, 5, simpleNodeLabel)
+	addPods(manager.podStore.Store, "node-0", simpleDaemonSetLabel2, 2)
+	addPods(manager.podStore.Store, "node-1", simpleDaemonSetLabel, 3)
+	addPods(manager.podStore.Store, "node-1", simpleDaemonSetLabel2, 1)
+	addPods(manager.podStore.Store, "node-4", simpleDaemonSetLabel, 1)
+	daemon := newDaemonSet("foo")
+	daemon.Spec.Template.Spec.NodeSelector = simpleNodeLabel
+	manager.dsStore.Add(daemon)
+	syncAndValidateDaemonSets(t, manager, daemon, podControl, 5, 4)
+}
+
+// DaemonSet with node selector should launch pods on nodes matching selector, but also deal with existing pods on nodes.
+func TestSelectorDaemonDealsWithExistingPods(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 5, nil)
+	addNodes(manager.nodeStore.Store, 5, 5, simpleNodeLabel)
+	addPods(manager.podStore.Store, "node-0", simpleDaemonSetLabel, 1)
+	addPods(manager.podStore.Store, "node-1", simpleDaemonSetLabel, 3)
+	addPods(manager.podStore.Store, "node-1", simpleDaemonSetLabel2, 2)
+	addPods(manager.podStore.Store, "node-2", simpleDaemonSetLabel, 4)
+	addPods(manager.podStore.Store, "node-6", simpleDaemonSetLabel, 13)
+	addPods(manager.podStore.Store, "node-7", simpleDaemonSetLabel2, 4)
+	addPods(manager.podStore.Store, "node-9", simpleDaemonSetLabel, 1)
+	addPods(manager.podStore.Store, "node-9", simpleDaemonSetLabel2, 1)
+	ds := newDaemonSet("foo")
+	ds.Spec.Template.Spec.NodeSelector = simpleNodeLabel
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 3, 20)
+}
+
+// DaemonSet with node selector which does not match any node labels should not launch pods.
+func TestBadSelectorDaemonDoesNothing(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 4, nil)
+	addNodes(manager.nodeStore.Store, 4, 3, simpleNodeLabel)
+	ds := newDaemonSet("foo")
+	ds.Spec.Template.Spec.NodeSelector = simpleNodeLabel2
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 0, 0)
+}
+
+// DaemonSet with node name should launch pod on node with corresponding name.
+func TestNameDaemonSetLaunchesPods(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 5, nil)
+	ds := newDaemonSet("foo")
+	ds.Spec.Template.Spec.NodeName = "node-0"
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 1, 0)
+}
+
+// DaemonSet with node name that does not exist should not launch pods.
+func TestBadNameDaemonSetDoesNothing(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 5, nil)
+	ds := newDaemonSet("foo")
+	ds.Spec.Template.Spec.NodeName = "node-10"
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 0, 0)
+}
+
+// DaemonSet with node selector, and node name, matching a node, should launch a pod on the node.
+func TestNameAndSelectorDaemonSetLaunchesPods(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 4, nil)
+	addNodes(manager.nodeStore.Store, 4, 3, simpleNodeLabel)
+	ds := newDaemonSet("foo")
+	ds.Spec.Template.Spec.NodeSelector = simpleNodeLabel
+	ds.Spec.Template.Spec.NodeName = "node-6"
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 1, 0)
+}
+
+// DaemonSet with node selector that matches some nodes, and node name that matches a different node, should do nothing.
+func TestInconsistentNameSelectorDaemonSetDoesNothing(t *testing.T) {
+	manager, podControl := newTestController()
+	addNodes(manager.nodeStore.Store, 0, 4, nil)
+	addNodes(manager.nodeStore.Store, 4, 3, simpleNodeLabel)
+	ds := newDaemonSet("foo")
+	ds.Spec.Template.Spec.NodeSelector = simpleNodeLabel
+	ds.Spec.Template.Spec.NodeName = "node-0"
+	manager.dsStore.Add(ds)
+	syncAndValidateDaemonSets(t, manager, ds, podControl, 0, 0)
+}

pkg/controller/daemon/doc.go

@@ -0,0 +1,19 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package daemon contains logic for watching and synchronizing
+// daemons.
+package daemon

pkg/controller/replication/replication_controller_test.go

@@ -27,6 +27,7 @@ import (
 
 	"k8s.io/kubernetes/pkg/api"
 	"k8s.io/kubernetes/pkg/api/testapi"
+	"k8s.io/kubernetes/pkg/apis/experimental"
 	"k8s.io/kubernetes/pkg/client/cache"
 	client "k8s.io/kubernetes/pkg/client/unversioned"
 	"k8s.io/kubernetes/pkg/client/unversioned/testclient"
@@ -69,6 +70,10 @@ func (f *FakePodControl) CreateReplica(namespace string, spec *api.ReplicationCo
 	return nil
 }
 
+func (f *FakePodControl) CreateReplicaOnNode(namespace string, daemon *experimental.DaemonSet, nodeName string) error {
+	return nil
+}
+
 func (f *FakePodControl) DeletePod(namespace string, podName string) error {
 	f.lock.Lock()
 	defer f.lock.Unlock()

test/e2e/daemon_set.go

@@ -0,0 +1,221 @@
+/*
+Copyright 2015 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package e2e
+
+import (
+	"fmt"
+	"time"
+
+	"k8s.io/kubernetes/pkg/api"
+	"k8s.io/kubernetes/pkg/apis/experimental"
+	client "k8s.io/kubernetes/pkg/client/unversioned"
+	"k8s.io/kubernetes/pkg/fields"
+	"k8s.io/kubernetes/pkg/labels"
+	"k8s.io/kubernetes/pkg/util/wait"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Daemon set", func() {
+	f := &Framework{BaseName: "daemonsets"}
+
+	BeforeEach(func() {
+		f.beforeEach()
+		err := clearNodeLabels(f.Client)
+		Expect(err).NotTo(HaveOccurred())
+	})
+
+	AfterEach(func() {
+		err := clearNodeLabels(f.Client)
+		Expect(err).NotTo(HaveOccurred())
+		f.afterEach()
+	})
+
+	It("should launch a daemon pod on every node of the cluster", func() {
+		testDaemonSets(f)
+	})
+})
+
+func clearNodeLabels(c *client.Client) error {
+	nodeClient := c.Nodes()
+	nodeList, err := nodeClient.List(labels.Everything(), fields.Everything())
+	if err != nil {
+		return err
+	}
+	for _, node := range nodeList.Items {
+		if len(node.Labels) != 0 {
+			node.Labels = map[string]string{}
+			newNode, err := nodeClient.Update(&node)
+			if err != nil {
+				return err
+			} else if len(newNode.Labels) != 0 {
+				return fmt.Errorf("Could not make node labels nil.")
+			}
+		}
+	}
+	return nil
+}
+
+func checkDaemonPodOnNodes(f *Framework, selector map[string]string, nodeNames []string) func() (bool, error) {
+	return func() (bool, error) {
+		podList, err := f.Client.Pods(f.Namespace.Name).List(labels.Set(selector).AsSelector(), fields.Everything())
+		if err != nil {
+			return false, nil
+		}
+		pods := podList.Items
+
+		nodesToPodCount := make(map[string]int)
+		for _, pod := range pods {
+			nodesToPodCount[pod.Spec.NodeName] += 1
+		}
+
+		// Ensure that exactly 1 pod is running on all nodes in nodeNames.
+		for _, nodeName := range nodeNames {
+			if nodesToPodCount[nodeName] != 1 {
+				return false, nil
+			}
+		}
+
+		// Ensure that sizes of the lists are the same. We've verified that every element of nodeNames is in
+		// nodesToPodCount, so verifying the lengths are equal ensures that there aren't pods running on any
+		// other nodes.
+		return len(nodesToPodCount) == len(nodeNames), nil
+	}
+}
+
+func checkRunningOnAllNodes(f *Framework, selector map[string]string) func() (bool, error) {
+	return func() (bool, error) {
+		nodeList, err := f.Client.Nodes().List(labels.Everything(), fields.Everything())
+		if err != nil {
+			return false, nil
+		}
+		nodeNames := make([]string, 0)
+		for _, node := range nodeList.Items {
+			nodeNames = append(nodeNames, node.Name)
+		}
+		return checkDaemonPodOnNodes(f, selector, nodeNames)()
+	}
+}
+
+func checkRunningOnNoNodes(f *Framework, selector map[string]string) func() (bool, error) {
+	return checkDaemonPodOnNodes(f, selector, make([]string, 0))
+}
+
+func testDaemonSets(f *Framework) {
+	ns := f.Namespace.Name
+	c := f.Client
+	simpleDSName := "simple-daemon-set"
+	image := "gcr.io/google_containers/serve_hostname:1.1"
+	label := map[string]string{"name": simpleDSName}
+	retryTimeout := 1 * time.Minute
+	retryInterval := 5 * time.Second
+
+	Logf("Creating simple daemon set %s", simpleDSName)
+	_, err := c.DaemonSets(ns).Create(&experimental.DaemonSet{
+		ObjectMeta: api.ObjectMeta{
+			Name: simpleDSName,
+		},
+		Spec: experimental.DaemonSetSpec{
+			Template: &api.PodTemplateSpec{
+				ObjectMeta: api.ObjectMeta{
+					Labels: label,
+				},
+				Spec: api.PodSpec{
+					Containers: []api.Container{
+						{
+							Name:  simpleDSName,
+							Image: image,
+							Ports: []api.ContainerPort{{ContainerPort: 9376}},
+						},
+					},
+				},
+			},
+		},
+	})
+	Expect(err).NotTo(HaveOccurred())
+
+	By("Check that daemon pods launch on every node of the cluster.")
+	Expect(err).NotTo(HaveOccurred())
+	err = wait.Poll(retryInterval, retryTimeout, checkRunningOnAllNodes(f, label))
+	Expect(err).NotTo(HaveOccurred(), "error waiting for daemon pod to start")
+
+	By("Stop a daemon pod, check that the daemon pod is revived.")
+	podClient := c.Pods(ns)
+
+	podList, err := podClient.List(labels.Set(label).AsSelector(), fields.Everything())
+	Expect(err).NotTo(HaveOccurred())
+	Expect(len(podList.Items)).To(BeNumerically(">", 0))
+	pod := podList.Items[0]
+	err = podClient.Delete(pod.Name, nil)
+	Expect(err).NotTo(HaveOccurred())
+	err = wait.Poll(retryInterval, retryTimeout, checkRunningOnAllNodes(f, label))
+	Expect(err).NotTo(HaveOccurred(), "error waiting for daemon pod to revive")
+
+	complexDSName := "complex-daemon-set"
+	complexLabel := map[string]string{"name": complexDSName}
+	nodeSelector := map[string]string{"color": "blue"}
+	Logf("Creating daemon with a node selector %s", complexDSName)
+	_, err = c.DaemonSets(ns).Create(&experimental.DaemonSet{
+		ObjectMeta: api.ObjectMeta{
+			Name: complexDSName,
+		},
+		Spec: experimental.DaemonSetSpec{
+			Selector: complexLabel,
+			Template: &api.PodTemplateSpec{
+				ObjectMeta: api.ObjectMeta{
+					Labels: complexLabel,
+				},
+				Spec: api.PodSpec{
+					NodeSelector: nodeSelector,
+					Containers: []api.Container{
+						{
+							Name:  complexDSName,
+							Image: image,
+							Ports: []api.ContainerPort{{ContainerPort: 9376}},
+						},
+					},
+				},
+			},
+		},
+	})
+	Expect(err).NotTo(HaveOccurred())
+
+	By("Initially, daemon pods should not be running on any nodes.")
+	err = wait.Poll(retryInterval, retryTimeout, checkRunningOnNoNodes(f, complexLabel))
+	Expect(err).NotTo(HaveOccurred(), "error waiting for daemon pods to be running on no nodes")
+
+	By("Change label of node, check that daemon pod is launched.")
+	nodeClient := c.Nodes()
+	nodeList, err := nodeClient.List(labels.Everything(), fields.Everything())
+	Expect(len(nodeList.Items)).To(BeNumerically(">", 0))
+	nodeList.Items[0].Labels = nodeSelector
+	newNode, err := nodeClient.Update(&nodeList.Items[0])
+	Expect(err).NotTo(HaveOccurred())
+	Expect(len(newNode.Labels)).To(Equal(1))
+	err = wait.Poll(retryInterval, retryTimeout, checkDaemonPodOnNodes(f, complexLabel, []string{newNode.Name}))
+	Expect(err).NotTo(HaveOccurred(), "error waiting for daemon pods to be running on new nodes")
+
+	By("remove the node selector and wait for")
+	newNode, err = nodeClient.Get(newNode.Name)
+	Expect(err).NotTo(HaveOccurred(), "error getting node")
+	newNode.Labels = map[string]string{}
+	newNode, err = nodeClient.Update(newNode)
+	Expect(err).NotTo(HaveOccurred())
+	Expect(wait.Poll(retryInterval, retryTimeout, checkRunningOnNoNodes(f, complexLabel))).
+		NotTo(HaveOccurred(), "error waiting for daemon pod to not be running on nodes")
+}