func NewMetricsGrabber(c *client.Client, kubelets bool, scheduler bool, controllers bool, apiServer bool) (*MetricsGrabber, error) {
registeredMaster := false
masterName := ""
nodeList, err := c.Nodes().List(api.ListOptions{})
if err != nil {
return nil, err
}
if len(nodeList.Items) < 1 {
glog.Warning("Can't find any Nodes in the API server to grab metrics from")
}
for _, node := range nodeList.Items {
if system.IsMasterNode(&node) {
registeredMaster = true
masterName = node.Name
break
}
}
if !registeredMaster {
scheduler = false
controllers = false
glog.Warningf("Master node is not registered. Grabbing metrics from Scheduler and ControllerManager is disabled.")
}
return &MetricsGrabber{
client: c,
grabFromApiServer: apiServer,
grabFromControllerManager: controllers,
grabFromKubelets: kubelets,
grabFromScheduler: scheduler,
masterName: masterName,
registeredMaster: registeredMaster,
}, nil
}
// monitorNodeStatus verifies node status are constantly updated by kubelet, and if not,
// post "NodeReady==ConditionUnknown". It also evicts all pods if node is not ready or
// not reachable for a long period of time.
func (nc *NodeController) monitorNodeStatus() error {
nodes, err := nc.kubeClient.Core().Nodes().List(api.ListOptions{})
if err != nil {
return err
}
for _, node := range nodes.Items {
if !nc.knownNodeSet.Has(node.Name) {
glog.V(1).Infof("NodeController observed a new Node: %#v", node)
nc.recordNodeEvent(node.Name, api.EventTypeNormal, "RegisteredNode", fmt.Sprintf("Registered Node %v in NodeController", node.Name))
nc.cancelPodEviction(node.Name)
nc.knownNodeSet.Insert(node.Name)
}
}
// If there's a difference between lengths of known Nodes and observed nodes
// we must have removed some Node.
if len(nc.knownNodeSet) != len(nodes.Items) {
observedSet := make(sets.String)
for _, node := range nodes.Items {
observedSet.Insert(node.Name)
}
deleted := nc.knownNodeSet.Difference(observedSet)
for nodeName := range deleted {
glog.V(1).Infof("NodeController observed a Node deletion: %v", nodeName)
nc.recordNodeEvent(nodeName, api.EventTypeNormal, "RemovingNode", fmt.Sprintf("Removing Node %v from NodeController", nodeName))
nc.evictPods(nodeName)
nc.knownNodeSet.Delete(nodeName)
}
}
seenReady := false
for i := range nodes.Items {
var gracePeriod time.Duration
var observedReadyCondition api.NodeCondition
var currentReadyCondition *api.NodeCondition
node := &nodes.Items[i]
for rep := 0; rep < nodeStatusUpdateRetry; rep++ {
gracePeriod, observedReadyCondition, currentReadyCondition, err = nc.tryUpdateNodeStatus(node)
if err == nil {
break
}
name := node.Name
node, err = nc.kubeClient.Core().Nodes().Get(name)
if err != nil {
glog.Errorf("Failed while getting a Node to retry updating NodeStatus. Probably Node %s was deleted.", name)
break
}
}
if err != nil {
glog.Errorf("Update status of Node %v from NodeController exceeds retry count."+
"Skipping - no pods will be evicted.", node.Name)
continue
}
decisionTimestamp := nc.now()
if currentReadyCondition != nil {
// Check eviction timeout against decisionTimestamp
if observedReadyCondition.Status == api.ConditionFalse &&
decisionTimestamp.After(nc.nodeStatusMap[node.Name].readyTransitionTimestamp.Add(nc.podEvictionTimeout)) {
if nc.evictPods(node.Name) {
glog.V(4).Infof("Evicting pods on node %s: %v is later than %v + %v", node.Name, decisionTimestamp, nc.nodeStatusMap[node.Name].readyTransitionTimestamp, nc.podEvictionTimeout)
}
}
if observedReadyCondition.Status == api.ConditionUnknown &&
decisionTimestamp.After(nc.nodeStatusMap[node.Name].probeTimestamp.Add(nc.podEvictionTimeout)) {
if nc.evictPods(node.Name) {
glog.V(4).Infof("Evicting pods on node %s: %v is later than %v + %v", node.Name, decisionTimestamp, nc.nodeStatusMap[node.Name].readyTransitionTimestamp, nc.podEvictionTimeout-gracePeriod)
}
}
if observedReadyCondition.Status == api.ConditionTrue {
// We do not treat a master node as a part of the cluster for network segmentation checking.
if !system.IsMasterNode(node) {
seenReady = true
}
if nc.cancelPodEviction(node.Name) {
glog.V(2).Infof("Node %s is ready again, cancelled pod eviction", node.Name)
}
}
// Report node event.
if currentReadyCondition.Status != api.ConditionTrue && observedReadyCondition.Status == api.ConditionTrue {
nc.recordNodeStatusChange(node, "NodeNotReady")
if err = nc.markAllPodsNotReady(node.Name); err != nil {
utilruntime.HandleError(fmt.Errorf("Unable to mark all pods NotReady on node %v: %v", node.Name, err))
}
}
// Check with the cloud provider to see if the node still exists. If it
// doesn't, delete the node immediately.
if currentReadyCondition.Status != api.ConditionTrue && nc.cloud != nil {
exists, err := nc.nodeExistsInCloudProvider(node.Name)
if err != nil {
glog.Errorf("Error determining if node %v exists in cloud: %v", node.Name, err)
continue
}
if !exists {
glog.V(2).Infof("Deleting node (no longer present in cloud provider): %s", node.Name)
nc.recordNodeEvent(node.Name, api.EventTypeNormal, "DeletingNode", fmt.Sprintf("Deleting Node %v because it's not present according to cloud provider", node.Name))
go func(nodeName string) {
defer utilruntime.HandleCrash()
// Kubelet is not reporting and Cloud Provider says node
// is gone. Delete it without worrying about grace
// periods.
if err := nc.forcefullyDeleteNode(nodeName); err != nil {
glog.Errorf("Unable to forcefully delete node %q: %v", nodeName, err)
}
}(node.Name)
continue
}
}
}
}
// NC don't see any Ready Node. We assume that the network is segmented and Nodes cannot connect to API server and
// update their statuses. NC enteres network segmentation mode and cancels all evictions in progress.
if !seenReady {
nc.networkSegmentationMode = true
nc.stopAllPodEvictions()
glog.V(2).Info("NodeController is entering network segmentation mode.")
} else {
if nc.networkSegmentationMode {
nc.forceUpdateAllProbeTimes()
nc.networkSegmentationMode = false
glog.V(2).Info("NodeController exited network segmentation mode.")
}
}
return nil
}