add NetworkStatus in NetworkPlugin interface for kubelet to consume

pkg/kubelet/kubelet.go

@@ -443,7 +443,7 @@ func NewMainKubelet(
 	klet.resourceAnalyzer = stats.NewResourceAnalyzer(klet, volumeStatsAggPeriod, klet.containerRuntime)
 
 	klet.pleg = pleg.NewGenericPLEG(klet.containerRuntime, plegChannelCapacity, plegRelistPeriod, klet.podCache, util.RealClock{})
-	klet.runtimeState = newRuntimeState(maxWaitForContainerRuntime, configureCBR0)
+	klet.runtimeState = newRuntimeState(maxWaitForContainerRuntime)
 	klet.updatePodCIDR(podCIDR)
 
 	// setup containerGC
@@ -3001,8 +3001,13 @@ func (kl *Kubelet) syncNetworkStatus() {
 			err = fmt.Errorf("Error configuring cbr0: %v", err)
 			glog.Error(err)
 		}
+		if err != nil {
+			kl.runtimeState.setNetworkState(err)
+			return
+		}
 	}
-	kl.runtimeState.setNetworkState(err)
+
+	kl.runtimeState.setNetworkState(kl.networkPlugin.NetworkStatus())
 }
 
 // Set addresses for the node.

pkg/kubelet/kubelet_test.go

@@ -125,7 +125,8 @@ func newTestKubelet(t *testing.T) *TestKubelet {
 
 	kubelet.hostname = testKubeletHostname
 	kubelet.nodeName = testKubeletHostname
-	kubelet.runtimeState = newRuntimeState(maxWaitForContainerRuntime, false)
+	kubelet.runtimeState = newRuntimeState(maxWaitForContainerRuntime)
+	kubelet.runtimeState.setNetworkState(nil)
 	kubelet.networkPlugin, _ = network.InitNetworkPlugin([]network.NetworkPlugin{}, "", nettest.NewFakeHost(nil))
 	if tempDir, err := ioutil.TempDir("/tmp", "kubelet_test."); err != nil {
 		t.Fatalf("can't make a temp rootdir: %v", err)

pkg/kubelet/network/kubenet/kubenet_linux.go

@@ -215,9 +215,8 @@ func (plugin *kubenetNetworkPlugin) SetUpPod(namespace string, name string, id k
 		return fmt.Errorf("Error reading pod bandwidth annotations: %v", err)
 	}
 
-	// Can't set up pods if we don't have a PodCIDR yet
-	if plugin.netConfig == nil {
-		return fmt.Errorf("Kubenet needs a PodCIDR to set up pods")
+	if err := plugin.NetworkStatus(); err != nil {
+		return fmt.Errorf("Kubenet cannot SetUpPod: %v", err)
 	}
 
 	runtime, ok := plugin.host.GetRuntime().(*dockertools.DockerManager)
@@ -310,6 +309,14 @@ func (plugin *kubenetNetworkPlugin) Status(namespace string, name string, id kub
 	return &network.PodNetworkStatus{IP: ip}, nil
 }
 
+func (plugin *kubenetNetworkPlugin) NetworkStatus() error {
+	// Can't set up pods if we don't have a PodCIDR yet
+	if plugin.netConfig == nil {
+		return fmt.Errorf("Kubenet does not have netConfig. This is most likely due to lack of PodCIDR")
+	}
+	return nil
+}
+
 func buildCNIRuntimeConf(podName string, podNs string, podInfraContainerID kubecontainer.ContainerID, podNetnsPath string) *libcni.RuntimeConf {
 	glog.V(4).Infof("Kubenet: using netns path %v", podNetnsPath)
 	glog.V(4).Infof("Kubenet: using podns path %v", podNs)

pkg/kubelet/network/plugins.go

@@ -74,6 +74,9 @@ type NetworkPlugin interface {
 
 	// Status is the method called to obtain the ipv4 or ipv6 addresses of the container
 	Status(namespace string, name string, podInfraContainerID kubecontainer.ContainerID) (*PodNetworkStatus, error)
+
+	// NetworkStatus returns error if the network plugin is in error state
+	NetworkStatus() error
 }
 
 // PodNetworkStatus stores the network status of a pod (currently just the primary IP address)
@@ -191,3 +194,7 @@ func (plugin *NoopNetworkPlugin) TearDownPod(namespace string, name string, id k
 func (plugin *NoopNetworkPlugin) Status(namespace string, name string, id kubecontainer.ContainerID) (*PodNetworkStatus, error) {
 	return nil, nil
 }
+
+func (plugin *NoopNetworkPlugin) NetworkStatus() error {
+	return nil
+}

pkg/kubelet/runtime.go

@@ -89,16 +89,11 @@ func (s *runtimeState) errors() []string {
 
 func newRuntimeState(
 	runtimeSyncThreshold time.Duration,
-	configureNetwork bool,
 ) *runtimeState {
-	var networkError error = nil
-	if configureNetwork {
-		networkError = fmt.Errorf("network state unknown")
-	}
 	return &runtimeState{
 		lastBaseRuntimeSync:      time.Time{},
 		baseRuntimeSyncThreshold: runtimeSyncThreshold,
-		networkError:             networkError,
+		networkError:             fmt.Errorf("network state unknown"),
 		internalError:            nil,
 	}
 }