// RunKubelet is responsible for setting up and running a kubelet. It is used in three different applications:
// 1 Integration tests
// 2 Kubelet binary
// 3 Standalone 'kubernetes' binary
// Eventually, #2 will be replaced with instances of #3
func RunKubelet(kcfg *KubeletConfig) {
kcfg.Hostname = util.GetHostname(kcfg.HostnameOverride)
if kcfg.KubeClient != nil {
kubelet.SetupEventSending(kcfg.KubeClient, kcfg.Hostname)
} else {
glog.Infof("No api server defined - no events will be sent.")
}
kubelet.SetupLogging()
kubelet.SetupCapabilities(kcfg.AllowPrivileged)
cfg := makePodSourceConfig(kcfg)
k, err := createAndInitKubelet(kcfg, cfg)
if err != nil {
glog.Errorf("Failed to create kubelet: %s", err)
return
}
// process pods and exit.
if kcfg.Runonce {
if _, err := k.RunOnce(cfg.Updates()); err != nil {
glog.Errorf("--runonce failed: %v", err)
}
} else {
startKubelet(k, cfg, kcfg)
}
}
// RunKubelet is responsible for setting up and running a kubelet. It is used in three different applications:
// 1 Integration tests
// 2 Kubelet binary
// 3 Standalone 'kubernetes' binary
// Eventually, #2 will be replaced with instances of #3
func RunKubelet(kcfg *KubeletConfig) {
kcfg.Hostname = util.GetHostname(kcfg.HostnameOverride)
kcfg.Recorder = record.FromSource(api.EventSource{Component: "kubelet", Host: kcfg.Hostname})
if kcfg.KubeClient != nil {
kubelet.SetupEventSending(kcfg.KubeClient, kcfg.Hostname)
} else {
glog.Infof("No api server defined - no events will be sent.")
}
kubelet.SetupLogging()
kubelet.SetupCapabilities(kcfg.AllowPrivileged)
credentialprovider.SetPreferredDockercfgPath(kcfg.RootDirectory)
podCfg := makePodSourceConfig(kcfg)
k, err := createAndInitKubelet(kcfg, podCfg)
if err != nil {
glog.Errorf("Failed to create kubelet: %s", err)
return
}
// process pods and exit.
if kcfg.Runonce {
if _, err := k.RunOnce(podCfg.Updates()); err != nil {
glog.Errorf("--runonce failed: %v", err)
}
} else {
startKubelet(k, podCfg, kcfg)
}
}
func SetupEventSending(client *client.Client) {
glog.Infof("Sending events to api server.")
hostname := util.GetHostname("")
record.StartRecording(client.Events(""),
api.EventSource{
Component: "kubelet",
Host: hostname,
})
}
// RunKubelet is responsible for setting up and running a kubelet. It is used in three different applications:
// 1 Integration tests
// 2 Kubelet binary
// 3 Standalone 'kubernetes' binary
// Eventually, #2 will be replaced with instances of #3
func RunKubelet(kcfg *KubeletConfig, builder KubeletBuilder) error {
kcfg.Hostname = util.GetHostname(kcfg.HostnameOverride)
eventBroadcaster := record.NewBroadcaster()
kcfg.Recorder = eventBroadcaster.NewRecorder(api.EventSource{Component: "kubelet", Host: kcfg.Hostname})
eventBroadcaster.StartLogging(glog.V(3).Infof)
if kcfg.KubeClient != nil {
glog.V(4).Infof("Sending events to api server.")
eventBroadcaster.StartRecordingToSink(kcfg.KubeClient.Events(""))
} else {
glog.Warning("No api server defined - no events will be sent to API server.")
}
capabilities.Setup(kcfg.AllowPrivileged, kcfg.HostNetworkSources)
credentialprovider.SetPreferredDockercfgPath(kcfg.RootDirectory)
if builder == nil {
builder = createAndInitKubelet
}
if kcfg.OSInterface == nil {
kcfg.OSInterface = kubecontainer.RealOS{}
}
k, podCfg, err := builder(kcfg)
if err != nil {
return fmt.Errorf("failed to create kubelet: %v", err)
}
// process pods and exit.
if kcfg.Runonce {
if _, err := k.RunOnce(podCfg.Updates()); err != nil {
return fmt.Errorf("runonce failed: %v", err)
}
glog.Infof("Started kubelet as runonce")
} else {
startKubelet(k, podCfg, kcfg)
glog.Infof("Started kubelet")
}
return nil
}
// KubeletConfig generates the appropriate Kubelet config for the given server arguments, or returns an
// error.
func (s *KubeletServer) KubeletConfig() (*KubeletConfig, error) {
hostNetworkSources, err := kubelet.GetValidatedSources(strings.Split(s.HostNetworkSources, ","))
if err != nil {
return nil, err
}
mounter := mount.New()
if s.Containerized {
glog.V(2).Info("Running kubelet in containerized mode (experimental)")
mounter = mount.NewNsenterMounter()
}
imageGCPolicy := kubelet.ImageGCPolicy{
HighThresholdPercent: s.ImageGCHighThresholdPercent,
LowThresholdPercent: s.ImageGCLowThresholdPercent,
}
diskSpacePolicy := kubelet.DiskSpacePolicy{
DockerFreeDiskMB: s.LowDiskSpaceThresholdMB,
RootFreeDiskMB: s.LowDiskSpaceThresholdMB,
}
var dockerExecHandler dockertools.ExecHandler
switch s.DockerExecHandler {
case "native":
dockerExecHandler = &dockertools.NativeExecHandler{}
case "nsenter":
dockerExecHandler = &dockertools.NsenterExecHandler{}
default:
glog.Warningf("Unknown Docker exec handler %q; defaulting to native", s.DockerExecHandler)
dockerExecHandler = &dockertools.NativeExecHandler{}
}
if s.TLSCertFile == "" && s.TLSPrivateKeyFile == "" {
s.TLSCertFile = path.Join(s.CertDirectory, "kubelet.crt")
s.TLSPrivateKeyFile = path.Join(s.CertDirectory, "kubelet.key")
if err := util.GenerateSelfSignedCert(util.GetHostname(s.HostnameOverride), s.TLSCertFile, s.TLSPrivateKeyFile); err != nil {
return nil, fmt.Errorf("unable to generate self signed cert: %v", err)
}
glog.V(4).Infof("Using self-signed cert (%s, %s)", s.TLSCertFile, s.TLSPrivateKeyFile)
}
tlsOptions := &kubelet.TLSOptions{
Config: &tls.Config{
// Change default from SSLv3 to TLSv1.0 (because of POODLE vulnerability).
MinVersion: tls.VersionTLS10,
// Populate PeerCertificates in requests, but don't yet reject connections without certificates.
ClientAuth: tls.RequestClientCert,
},
CertFile: s.TLSCertFile,
KeyFile: s.TLSPrivateKeyFile,
}
return &KubeletConfig{
Address: s.Address,
AllowPrivileged: s.AllowPrivileged,
HostNetworkSources: hostNetworkSources,
HostnameOverride: s.HostnameOverride,
RootDirectory: s.RootDirectory,
ConfigFile: s.Config,
ManifestURL: s.ManifestURL,
FileCheckFrequency: s.FileCheckFrequency,
HTTPCheckFrequency: s.HTTPCheckFrequency,
PodInfraContainerImage: s.PodInfraContainerImage,
SyncFrequency: s.SyncFrequency,
RegistryPullQPS: s.RegistryPullQPS,
RegistryBurst: s.RegistryBurst,
MinimumGCAge: s.MinimumGCAge,
MaxPerPodContainerCount: s.MaxPerPodContainerCount,
MaxContainerCount: s.MaxContainerCount,
RegisterNode: s.RegisterNode,
ClusterDomain: s.ClusterDomain,
ClusterDNS: s.ClusterDNS,
Runonce: s.RunOnce,
Port: s.Port,
ReadOnlyPort: s.ReadOnlyPort,
EnableServer: s.EnableServer,
EnableDebuggingHandlers: s.EnableDebuggingHandlers,
MasterServiceNamespace: s.MasterServiceNamespace,
VolumePlugins: ProbeVolumePlugins(),
NetworkPlugins: ProbeNetworkPlugins(),
NetworkPluginName: s.NetworkPluginName,
StreamingConnectionIdleTimeout: s.StreamingConnectionIdleTimeout,
TLSOptions: tlsOptions,
ImageGCPolicy: imageGCPolicy,
DiskSpacePolicy: diskSpacePolicy,
NodeStatusUpdateFrequency: s.NodeStatusUpdateFrequency,
ResourceContainer: s.ResourceContainer,
CgroupRoot: s.CgroupRoot,
ContainerRuntime: s.ContainerRuntime,
Mounter: mounter,
DockerDaemonContainer: s.DockerDaemonContainer,
ConfigureCBR0: s.ConfigureCBR0,
MaxPods: s.MaxPods,
DockerExecHandler: dockerExecHandler,
}, nil
}
// Run runs the specified KubeletServer. This should never exit.
func (s *KubeletServer) Run(_ []string) error {
util.ReallyCrash = s.ReallyCrashForTesting
rand.Seed(time.Now().UTC().UnixNano())
// TODO(vmarmol): Do this through container config.
if err := util.ApplyOomScoreAdj(0, s.OOMScoreAdj); err != nil {
glog.Info(err)
}
client, err := s.createAPIServerClient()
if err != nil && len(s.APIServerList) > 0 {
glog.Warningf("No API client: %v", err)
}
glog.Infof("Using root directory: %v", s.RootDirectory)
credentialprovider.SetPreferredDockercfgPath(s.RootDirectory)
cadvisorInterface, err := cadvisor.New(s.CadvisorPort)
if err != nil {
return err
}
imageGCPolicy := kubelet.ImageGCPolicy{
HighThresholdPercent: s.ImageGCHighThresholdPercent,
LowThresholdPercent: s.ImageGCLowThresholdPercent,
}
cloud := cloudprovider.InitCloudProvider(s.CloudProvider, s.CloudConfigFile)
glog.Infof("Successfully initialized cloud provider: %q from the config file: %q\n", s.CloudProvider, s.CloudConfigFile)
hostNetworkSources, err := kubelet.GetValidatedSources(strings.Split(s.HostNetworkSources, ","))
if err != nil {
return err
}
if s.TLSCertFile == "" && s.TLSPrivateKeyFile == "" {
s.TLSCertFile = path.Join(s.CertDirectory, "kubelet.crt")
s.TLSPrivateKeyFile = path.Join(s.CertDirectory, "kubelet.key")
if err := util.GenerateSelfSignedCert(util.GetHostname(s.HostnameOverride), s.TLSCertFile, s.TLSPrivateKeyFile); err != nil {
glog.Fatalf("Unable to generate self signed cert: %v", err)
}
glog.Infof("Using self-signed cert (%s, %s)", s.TLSCertFile, s.TLSPrivateKeyFile)
}
tlsOptions := &kubelet.TLSOptions{
Config: &tls.Config{
// Change default from SSLv3 to TLSv1.0 (because of POODLE vulnerability).
MinVersion: tls.VersionTLS10,
// Populate PeerCertificates in requests, but don't yet reject connections without certificates.
ClientAuth: tls.RequestClientCert,
},
CertFile: s.TLSCertFile,
KeyFile: s.TLSPrivateKeyFile,
}
kcfg := KubeletConfig{
Address: s.Address,
AllowPrivileged: s.AllowPrivileged,
HostNetworkSources: hostNetworkSources,
HostnameOverride: s.HostnameOverride,
RootDirectory: s.RootDirectory,
ConfigFile: s.Config,
ManifestURL: s.ManifestURL,
FileCheckFrequency: s.FileCheckFrequency,
HTTPCheckFrequency: s.HTTPCheckFrequency,
PodInfraContainerImage: s.PodInfraContainerImage,
SyncFrequency: s.SyncFrequency,
RegistryPullQPS: s.RegistryPullQPS,
RegistryBurst: s.RegistryBurst,
MinimumGCAge: s.MinimumGCAge,
MaxPerPodContainerCount: s.MaxPerPodContainerCount,
MaxContainerCount: s.MaxContainerCount,
ClusterDomain: s.ClusterDomain,
ClusterDNS: s.ClusterDNS,
Runonce: s.RunOnce,
Port: s.Port,
ReadOnlyPort: s.ReadOnlyPort,
CadvisorInterface: cadvisorInterface,
EnableServer: s.EnableServer,
EnableDebuggingHandlers: s.EnableDebuggingHandlers,
DockerClient: dockertools.ConnectToDockerOrDie(s.DockerEndpoint),
KubeClient: client,
MasterServiceNamespace: s.MasterServiceNamespace,
VolumePlugins: ProbeVolumePlugins(),
NetworkPlugins: ProbeNetworkPlugins(),
NetworkPluginName: s.NetworkPluginName,
StreamingConnectionIdleTimeout: s.StreamingConnectionIdleTimeout,
TLSOptions: tlsOptions,
ImageGCPolicy: imageGCPolicy,
Cloud: cloud,
NodeStatusUpdateFrequency: s.NodeStatusUpdateFrequency,
ResourceContainer: s.ResourceContainer,
}
RunKubelet(&kcfg, nil)
if s.HealthzPort > 0 {
healthz.DefaultHealthz()
go util.Forever(func() {
err := http.ListenAndServe(net.JoinHostPort(s.HealthzBindAddress.String(), strconv.Itoa(s.HealthzPort)), nil)
if err != nil {
glog.Errorf("Starting health server failed: %v", err)
}
}, 5*time.Second)
}
// runs forever
select {}
}