Merge pull request #125 from galal-hussein/add_kubelet_sidekick

Add services sidekick container

cluster/cluster.go

@@ -45,6 +45,7 @@ const (
 	DNSMasqImage               = "dnsmasq_image"
 	KubeDNSSidecarImage        = "kubedns_sidecar_image"
 	KubeDNSAutoScalerImage     = "kubedns_autoscaler_image"
+	ServiceSidekickImage       = "service_sidekick_image"
 )
 
 func (c *Cluster) DeployClusterPlanes() error {
@@ -53,11 +54,18 @@ func (c *Cluster) DeployClusterPlanes() error {
 	if err != nil {
 		return fmt.Errorf("[etcd] Failed to bring up Etcd Plane: %v", err)
 	}
-	err = services.RunControlPlane(c.ControlPlaneHosts, c.EtcdHosts, c.Services)
+	err = services.RunControlPlane(c.ControlPlaneHosts,
+		c.EtcdHosts,
+		c.Services,
+		c.SystemImages[ServiceSidekickImage])
 	if err != nil {
 		return fmt.Errorf("[controlPlane] Failed to bring up Control Plane: %v", err)
 	}
-	err = services.RunWorkerPlane(c.ControlPlaneHosts, c.WorkerHosts, c.Services, c.SystemImages[NginxProxyImage])
+	err = services.RunWorkerPlane(c.ControlPlaneHosts,
+		c.WorkerHosts,
+		c.Services,
+		c.SystemImages[NginxProxyImage],
+		c.SystemImages[ServiceSidekickImage])
 	if err != nil {
 		return fmt.Errorf("[workerPlane] Failed to bring up Worker Plane: %v", err)
 	}
@@ -157,6 +165,7 @@ func (c *Cluster) setClusterImageDefaults() {
 		DNSMasqImage:           DefaultDNSMasqImage,
 		KubeDNSSidecarImage:    DefaultKubeDNSSidecarImage,
 		KubeDNSAutoScalerImage: DefaultKubeDNSAutoScalerImage,
+		ServiceSidekickImage:   DefaultServiceSidekickImage,
 	}
 	for k, v := range systemImagesDefaultsMap {
 		setDefaultIfEmptyMapValue(c.SystemImages, k, v)

cluster/defaults.go

@@ -13,10 +13,11 @@ const (
 
 	DefaultNetworkPlugin = "flannel"
 
-	DefaultInfraContainerImage = "gcr.io/google_containers/pause-amd64:3.0"
-	DefaultAplineImage         = "alpine:latest"
-	DefaultNginxProxyImage     = "rancher/rke-nginx-proxy:0.1.0"
-	DefaultCertDownloaderImage = "rancher/rke-cert-deployer:0.1.0"
+	DefaultInfraContainerImage  = "gcr.io/google_containers/pause-amd64:3.0"
+	DefaultAplineImage          = "alpine:latest"
+	DefaultNginxProxyImage      = "rancher/rke-nginx-proxy:0.1.0"
+	DefaultCertDownloaderImage  = "rancher/rke-cert-deployer:0.1.0"
+	DefaultServiceSidekickImage = "rancher/rke-service-sidekick:0.1.0"
 
 	DefaultFlannelImage           = "quay.io/coreos/flannel:v0.9.1"
 	DefaultFlannelCNIImage        = "quay.io/coreos/flannel-cni:v0.2.0"

docker/docker.go

@@ -20,7 +20,7 @@ var K8sDockerVersions = map[string][]string{
 }
 
 func DoRunContainer(dClient *client.Client, imageCfg *container.Config, hostCfg *container.HostConfig, containerName string, hostname string, plane string) error {
-	isRunning, err := IsContainerRunning(dClient, hostname, containerName)
+	isRunning, err := IsContainerRunning(dClient, hostname, containerName, false)
 	if err != nil {
 		return err
 	}
@@ -56,7 +56,7 @@ func DoRunContainer(dClient *client.Client, imageCfg *container.Config, hostCfg
 
 func DoRollingUpdateContainer(dClient *client.Client, imageCfg *container.Config, hostCfg *container.HostConfig, containerName, hostname, plane string) error {
 	logrus.Debugf("[%s] Checking for deployed [%s]", plane, containerName)
-	isRunning, err := IsContainerRunning(dClient, hostname, containerName)
+	isRunning, err := IsContainerRunning(dClient, hostname, containerName, false)
 	if err != nil {
 		return err
 	}
@@ -115,9 +115,9 @@ func DoRemoveContainer(dClient *client.Client, containerName, hostname string) e
 	return nil
 }
 
-func IsContainerRunning(dClient *client.Client, hostname string, containerName string) (bool, error) {
+func IsContainerRunning(dClient *client.Client, hostname string, containerName string, all bool) (bool, error) {
 	logrus.Debugf("Checking if container [%s] is running on host [%s]", containerName, hostname)
-	containers, err := dClient.ContainerList(context.Background(), types.ContainerListOptions{})
+	containers, err := dClient.ContainerList(context.Background(), types.ContainerListOptions{All: all})
 	if err != nil {
 		return false, fmt.Errorf("Can't get Docker containers for host [%s]: %v", hostname, err)
 

package/service-sidekick/Dockerfile

@@ -0,0 +1,7 @@
+FROM scratch
+
+VOLUME /opt/rke
+
+COPY entrypoint.sh /opt/rke/entrypoint.sh
+
+CMD /bin/true

package/service-sidekick/build-and-push.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+ACCT=${ACCT:-rancher}
+
+docker build -t $ACCT/rke-service-sidekick:0.1.0 .
+docker push $ACCT/rke-service-sidekick:0.1.0

package/service-sidekick/entrypoint.sh

@@ -0,0 +1,22 @@
+#!/bin/bash -x
+
+if [ "$1" == "kubelet" ]; then
+    for i in $(DOCKER_API_VERSION=1.24 ./docker info 2>&1  | grep -i 'docker root dir' | cut -f2 -d:) /var/lib/docker /run /var/run; do
+        for m in $(tac /proc/mounts | awk '{print $2}' | grep ^${i}/); do
+            if [ "$m" != "/var/run/nscd" ] && [ "$m" != "/run/nscd" ]; then
+                umount $m || true
+            fi
+        done
+    done
+    mount --rbind /host/dev /dev
+    mount -o rw,remount /sys/fs/cgroup 2>/dev/null || true
+    for i in /sys/fs/cgroup/*; do
+        if [ -d $i ]; then
+             mkdir -p $i/kubepods
+        fi
+    done
+    CGROUPDRIVER=$(docker info | grep -i 'cgroup driver' | awk '{print $3}')
+    exec "$@" --cgroup-driver=$CGROUPDRIVER
+fi
+
+exec "$@"

pki/deploy.go

@@ -86,7 +86,7 @@ func doRunDeployer(host *hosts.Host, containerEnv []string, certDownloaderImage
 	}
 	logrus.Debugf("[certificates] Successfully started Certificate deployer container: %s", resp.ID)
 	for {
-		isDeployerRunning, err := docker.IsContainerRunning(host.DClient, host.Address, CrtDownloaderContainer)
+		isDeployerRunning, err := docker.IsContainerRunning(host.DClient, host.Address, CrtDownloaderContainer, false)
 		if err != nil {
 			return err
 		}

services/controlplane.go

@@ -6,7 +6,7 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-func RunControlPlane(controlHosts []*hosts.Host, etcdHosts []*hosts.Host, controlServices v3.RKEConfigServices) error {
+func RunControlPlane(controlHosts, etcdHosts []*hosts.Host, controlServices v3.RKEConfigServices, sidekickImage string) error {
 	logrus.Infof("[%s] Building up Controller Plane..", ControlRole)
 	for _, host := range controlHosts {
 
@@ -15,6 +15,10 @@ func RunControlPlane(controlHosts []*hosts.Host, etcdHosts []*hosts.Host, contro
 				return err
 			}
 		}
+		// run sidekick
+		if err := runSidekick(host, sidekickImage); err != nil {
+			return err
+		}
 		// run kubeapi
 		err := runKubeAPI(host, etcdHosts, controlServices.KubeAPI)
 		if err != nil {
@@ -66,6 +70,10 @@ func RemoveControlPlane(controlHosts []*hosts.Host, force bool) error {
 			if err := removeKubeproxy(host); err != nil {
 				return nil
 			}
+			// remove Sidekick
+			if err := removeSidekick(host); err != nil {
+				return err
+			}
 		}
 	}
 	logrus.Infof("[%s] Successfully teared down Controller Plane..", ControlRole)

services/kubeapi.go

@@ -24,7 +24,8 @@ func removeKubeAPI(host *hosts.Host) error {
 func buildKubeAPIConfig(host *hosts.Host, kubeAPIService v3.KubeAPIService, etcdConnString string) (*container.Config, *container.HostConfig) {
 	imageCfg := &container.Config{
 		Image: kubeAPIService.Image,
-		Entrypoint: []string{"kube-apiserver",
+		Entrypoint: []string{"/opt/rke/entrypoint.sh",
+			"kube-apiserver",
 			"--insecure-bind-address=127.0.0.1",
 			"--bind-address=0.0.0.0",
 			"--insecure-port=8080",
@@ -44,6 +45,9 @@ func buildKubeAPIConfig(host *hosts.Host, kubeAPIService v3.KubeAPIService, etcd
 			"--service-account-key-file=" + pki.KubeAPIKeyPath},
 	}
 	hostCfg := &container.HostConfig{
+		VolumesFrom: []string{
+			SidekickContainerName,
+		},
 		Binds: []string{
 			"/etc/kubernetes:/etc/kubernetes",
 		},

services/kubecontroller.go

@@ -22,7 +22,8 @@ func removeKubeController(host *hosts.Host) error {
 func buildKubeControllerConfig(kubeControllerService v3.KubeControllerService) (*container.Config, *container.HostConfig) {
 	imageCfg := &container.Config{
 		Image: kubeControllerService.Image,
-		Entrypoint: []string{"kube-controller-manager",
+		Entrypoint: []string{"/opt/rke/entrypoint.sh",
+			"kube-controller-manager",
 			"--address=0.0.0.0",
 			"--cloud-provider=",
 			"--leader-elect=true",
@@ -39,6 +40,9 @@ func buildKubeControllerConfig(kubeControllerService v3.KubeControllerService) (
 		},
 	}
 	hostCfg := &container.HostConfig{
+		VolumesFrom: []string{
+			SidekickContainerName,
+		},
 		Binds: []string{
 			"/etc/kubernetes:/etc/kubernetes",
 		},

services/kubelet.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 
 	"github.com/docker/docker/api/types/container"
-	"github.com/docker/go-connections/nat"
 	"github.com/rancher/rke/docker"
 	"github.com/rancher/rke/hosts"
 	"github.com/rancher/rke/pki"
@@ -23,12 +22,12 @@ func removeKubelet(host *hosts.Host) error {
 func buildKubeletConfig(host *hosts.Host, kubeletService v3.KubeletService) (*container.Config, *container.HostConfig) {
 	imageCfg := &container.Config{
 		Image: kubeletService.Image,
-		Entrypoint: []string{"kubelet",
+		Entrypoint: []string{"/opt/rke/entrypoint.sh",
+			"kubelet",
 			"--v=2",
 			"--address=0.0.0.0",
 			"--cluster-domain=" + kubeletService.ClusterDomain,
 			"--pod-infra-container-image=" + kubeletService.InfraContainerImage,
-			"--cgroup-driver=cgroupfs",
 			"--cgroups-per-qos=True",
 			"--enforce-node-allocatable=",
 			"--hostname-override=" + host.HostnameOverride,
@@ -54,30 +53,24 @@ func buildKubeletConfig(host *hosts.Host, kubeletService v3.KubeletService) (*co
 		}
 	}
 	hostCfg := &container.HostConfig{
+		VolumesFrom: []string{
+			SidekickContainerName,
+		},
 		Binds: []string{
 			"/etc/kubernetes:/etc/kubernetes",
 			"/etc/cni:/etc/cni:ro",
 			"/opt/cni:/opt/cni:ro",
 			"/etc/resolv.conf:/etc/resolv.conf",
-			"/sys:/sys:ro",
+			"/sys:/sys",
 			"/var/lib/docker:/var/lib/docker:rw",
 			"/var/lib/kubelet:/var/lib/kubelet:shared",
 			"/var/run:/var/run:rw",
 			"/run:/run",
-			"/dev:/host/dev",
-			"/sys/fs/cgroup:/sys/fs/cgroup:rw"},
+			"/dev:/host/dev"},
 		NetworkMode:   "host",
 		PidMode:       "host",
 		Privileged:    true,
 		RestartPolicy: container.RestartPolicy{Name: "always"},
-		PortBindings: nat.PortMap{
-			"8080/tcp": []nat.PortBinding{
-				{
-					HostIP:   "0.0.0.0",
-					HostPort: "8080",
-				},
-			},
-		},
 	}
 	for arg, value := range kubeletService.ExtraArgs {
 		cmd := fmt.Sprintf("--%s=%s", arg, value)

services/kubeproxy.go

@@ -22,13 +22,17 @@ func removeKubeproxy(host *hosts.Host) error {
 func buildKubeproxyConfig(host *hosts.Host, kubeproxyService v3.KubeproxyService) (*container.Config, *container.HostConfig) {
 	imageCfg := &container.Config{
 		Image: kubeproxyService.Image,
-		Entrypoint: []string{"kube-proxy",
+		Entrypoint: []string{"/opt/rke/entrypoint.sh",
+			"kube-proxy",
 			"--v=2",
 			"--healthz-bind-address=0.0.0.0",
 			"--kubeconfig=" + pki.KubeProxyConfigPath,
 		},
 	}
 	hostCfg := &container.HostConfig{
+		VolumesFrom: []string{
+			SidekickContainerName,
+		},
 		Binds: []string{
 			"/etc/kubernetes:/etc/kubernetes",
 		},

services/scheduler.go

@@ -22,7 +22,8 @@ func removeScheduler(host *hosts.Host) error {
 func buildSchedulerConfig(host *hosts.Host, schedulerService v3.SchedulerService) (*container.Config, *container.HostConfig) {
 	imageCfg := &container.Config{
 		Image: schedulerService.Image,
-		Entrypoint: []string{"kube-scheduler",
+		Entrypoint: []string{"/opt/rke/entrypoint.sh",
+			"kube-scheduler",
 			"--leader-elect=true",
 			"--v=2",
 			"--address=0.0.0.0",
@@ -30,6 +31,9 @@ func buildSchedulerConfig(host *hosts.Host, schedulerService v3.SchedulerService
 		},
 	}
 	hostCfg := &container.HostConfig{
+		VolumesFrom: []string{
+			SidekickContainerName,
+		},
 		Binds: []string{
 			"/etc/kubernetes:/etc/kubernetes",
 		},

services/services.go

@@ -3,6 +3,11 @@ package services
 import (
 	"fmt"
 	"net"
+
+	"github.com/docker/docker/api/types/container"
+	"github.com/rancher/rke/docker"
+	"github.com/rancher/rke/hosts"
+	"github.com/sirupsen/logrus"
 )
 
 const (
@@ -17,6 +22,7 @@ const (
 	SchedulerContainerName      = "scheduler"
 	EtcdContainerName           = "etcd"
 	NginxProxyContainerName     = "nginx-proxy"
+	SidekickContainerName       = "service-sidekick"
 )
 
 func GetKubernetesServiceIP(serviceClusterRange string) (net.IP, error) {
@@ -33,3 +39,36 @@ func GetKubernetesServiceIP(serviceClusterRange string) (net.IP, error) {
 	}
 	return ip, nil
 }
+
+func buildSidekickConfig(sidekickImage string) (*container.Config, *container.HostConfig) {
+	imageCfg := &container.Config{
+		Image: sidekickImage,
+	}
+	hostCfg := &container.HostConfig{
+		NetworkMode: "none",
+	}
+	return imageCfg, hostCfg
+}
+
+func runSidekick(host *hosts.Host, sidekickImage string) error {
+	isRunning, err := docker.IsContainerRunning(host.DClient, host.Address, SidekickContainerName, true)
+	if err != nil {
+		return err
+	}
+	if isRunning {
+		logrus.Infof("[sidekick] Sidekick container already created on host [%s]", host.Address)
+		return nil
+	}
+	imageCfg, hostCfg := buildSidekickConfig(sidekickImage)
+	if err := docker.PullImage(host.DClient, host.Address, sidekickImage); err != nil {
+		return err
+	}
+	if _, err := docker.CreateContiner(host.DClient, host.Address, SidekickContainerName, imageCfg, hostCfg); err != nil {
+		return err
+	}
+	return nil
+}
+
+func removeSidekick(host *hosts.Host) error {
+	return docker.DoRemoveContainer(host.DClient, SidekickContainerName, host.Address)
+}

services/workerplane.go

@@ -6,9 +6,14 @@ import (
 	"github.com/sirupsen/logrus"
 )
 
-func RunWorkerPlane(controlHosts []*hosts.Host, workerHosts []*hosts.Host, workerServices v3.RKEConfigServices, nginxProxyImage string) error {
+func RunWorkerPlane(controlHosts, workerHosts []*hosts.Host, workerServices v3.RKEConfigServices, nginxProxyImage, sidekickImage string) error {
 	logrus.Infof("[%s] Building up Worker Plane..", WorkerRole)
 	for _, host := range controlHosts {
+		// run sidekick
+		if err := runSidekick(host, sidekickImage); err != nil {
+			return err
+		}
+		// run kubelet
 		// only one master for now
 		if err := runKubelet(host, workerServices.Kubelet); err != nil {
 			return err
@@ -24,6 +29,10 @@ func RunWorkerPlane(controlHosts []*hosts.Host, workerHosts []*hosts.Host, worke
 				return err
 			}
 		}
+		// run sidekick
+		if err := runSidekick(host, sidekickImage); err != nil {
+			return err
+		}
 		// run kubelet
 		if err := runKubelet(host, workerServices.Kubelet); err != nil {
 			return err
@@ -55,6 +64,9 @@ func RemoveWorkerPlane(workerHosts []*hosts.Host, force bool) error {
 		if err := removeNginxProxy(host); err != nil {
 			return err
 		}
+		if err := removeSidekick(host); err != nil {
+			return err
+		}
 		logrus.Infof("[%s] Successfully teared down Worker Plane..", WorkerRole)
 	}