Add disable flags for control components (#2900)

pkg/agent/config/config.go

@@ -406,6 +406,7 @@ func get(envInfo *cmds.Agent, proxy proxy.Proxy) (*config.Node, error) {
 		SELinux:                  envInfo.EnableSELinux,
 		ContainerRuntimeEndpoint: envInfo.ContainerRuntimeEndpoint,
 		FlannelBackend:           controlConfig.FlannelBackend,
+		ServerHTTPSPort:          controlConfig.HTTPSPort,
 	}
 	nodeConfig.FlannelIface = flannelIface
 	nodeConfig.Images = filepath.Join(envInfo.DataDir, "agent", "images")

pkg/agent/loadbalancer/loadbalancer.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"net"
 	"path/filepath"
+	"strconv"
 	"sync"
 
 	"github.com/google/tcpproxy"
@@ -26,15 +27,19 @@ type LoadBalancer struct {
 	randomServers         []string
 	currentServerAddress  string
 	nextServerIndex       int
+	Listener              net.Listener
 }
 
+const RandomPort = 0
+
 var (
 	SupervisorServiceName = version.Program + "-agent-load-balancer"
 	APIServerServiceName  = version.Program + "-api-server-agent-load-balancer"
+	ETCDServerServiceName = version.Program + "-etcd-server-load-balancer"
 )
 
-func New(dataDir, serviceName, serverURL string) (_lb *LoadBalancer, _err error) {
-	listener, err := net.Listen("tcp", "127.0.0.1:0")
+func New(dataDir, serviceName, serverURL string, lbServerPort int) (_lb *LoadBalancer, _err error) {
+	listener, err := net.Listen("tcp", "127.0.0.1:"+strconv.Itoa(lbServerPort))
 	defer func() {
 		if _err != nil {
 			logrus.Warnf("Error starting load balancer: %s", _err)

pkg/agent/loadbalancer/loadbalancer_test.go

@@ -105,7 +105,7 @@ func TestFailOver(t *testing.T) {
 		DataDir:   tmpDir,
 	}
 
-	lb, err := New(cfg.DataDir, SupervisorServiceName, cfg.ServerURL)
+	lb, err := New(cfg.DataDir, SupervisorServiceName, cfg.ServerURL, RandomPort)
 	if err != nil {
 		assertEqual(t, err, nil)
 	}
@@ -156,7 +156,7 @@ func TestFailFast(t *testing.T) {
 		DataDir:   tmpDir,
 	}
 
-	lb, err := New(cfg.DataDir, SupervisorServiceName, cfg.ServerURL)
+	lb, err := New(cfg.DataDir, SupervisorServiceName, cfg.ServerURL, RandomPort)
 	if err != nil {
 		assertEqual(t, err, nil)
 	}

pkg/agent/proxy/apiproxy.go

@@ -17,19 +17,21 @@ type Proxy interface {
 	SupervisorURL() string
 	SupervisorAddresses() []string
 	APIServerURL() string
+	IsAPIServerLBEnabled() bool
 }
 
-func NewAPIProxy(enabled bool, dataDir, supervisorURL string) (Proxy, error) {
-	p := &proxy{
+func NewAPIProxy(enabled bool, dataDir, supervisorURL string, lbServerPort int) (Proxy, error) {
+	p := proxy{
 		lbEnabled:            enabled,
 		dataDir:              dataDir,
 		initialSupervisorURL: supervisorURL,
 		supervisorURL:        supervisorURL,
 		apiServerURL:         supervisorURL,
+		lbServerPort:         lbServerPort,
 	}
 
 	if enabled {
-		lb, err := loadbalancer.New(dataDir, loadbalancer.SupervisorServiceName, supervisorURL)
+		lb, err := loadbalancer.New(dataDir, loadbalancer.SupervisorServiceName, supervisorURL, p.lbServerPort)
 		if err != nil {
 			return nil, err
 		}
@@ -45,12 +47,13 @@ func NewAPIProxy(enabled bool, dataDir, supervisorURL string) (Proxy, error) {
 	p.fallbackSupervisorAddress = u.Host
 	p.supervisorPort = u.Port()
 
-	return p, nil
+	return &p, nil
 }
 
 type proxy struct {
-	dataDir   string
-	lbEnabled bool
+	dataDir      string
+	lbEnabled    bool
+	lbServerPort int
 
 	initialSupervisorURL      string
 	supervisorURL             string
@@ -71,14 +74,12 @@ func (p *proxy) Update(addresses []string) {
 	if p.apiServerEnabled {
 		supervisorAddresses = p.setSupervisorPort(supervisorAddresses)
 	}
-
 	if p.apiServerLB != nil {
 		p.apiServerLB.Update(apiServerAddresses)
 	}
 	if p.supervisorLB != nil {
 		p.supervisorLB.Update(supervisorAddresses)
 	}
-
 	p.supervisorAddresses = supervisorAddresses
 }
 
@@ -106,7 +107,11 @@ func (p *proxy) StartAPIServerProxy(port int) error {
 	p.apiServerEnabled = true
 
 	if p.lbEnabled {
-		lb, err := loadbalancer.New(p.dataDir, loadbalancer.APIServerServiceName, p.apiServerURL)
+		lbServerPort := p.lbServerPort
+		if lbServerPort != 0 {
+			lbServerPort = lbServerPort + 1
+		}
+		lb, err := loadbalancer.New(p.dataDir, loadbalancer.APIServerServiceName, p.apiServerURL, lbServerPort)
 		if err != nil {
 			return err
 		}
@@ -131,3 +136,7 @@ func (p *proxy) SupervisorAddresses() []string {
 func (p *proxy) APIServerURL() string {
 	return p.apiServerURL
 }
+
+func (p *proxy) IsAPIServerLBEnabled() bool {
+	return p.apiServerLB != nil
+}

pkg/agent/run.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"io/ioutil"
+	"net/url"
 	"os"
 	"path/filepath"
 	"strings"
@@ -89,12 +90,7 @@ func run(ctx context.Context, cfg cmds.Agent, proxy proxy.Proxy) error {
 			return err
 		}
 	}
-
-	if err := tunnel.Setup(ctx, nodeConfig, proxy); err != nil {
-		return err
-	}
-
-	if err := agent.Agent(&nodeConfig.AgentConfig); err != nil {
+	if err := setupTunnelAndRunAgent(ctx, nodeConfig, cfg, proxy); err != nil {
 		return err
 	}
 
@@ -148,7 +144,7 @@ func Run(ctx context.Context, cfg cmds.Agent) error {
 		return err
 	}
 
-	proxy, err := proxy.NewAPIProxy(!cfg.DisableLoadBalancer, agentDir, cfg.ServerURL)
+	proxy, err := proxy.NewAPIProxy(!cfg.DisableLoadBalancer, agentDir, cfg.ServerURL, cfg.LBServerPort)
 	if err != nil {
 		return err
 	}
@@ -167,7 +163,6 @@ func Run(ctx context.Context, cfg cmds.Agent) error {
 		cfg.Token = newToken.String()
 		break
 	}
-
 	systemd.SdNotify(true, "READY=1\n")
 	return run(ctx, cfg, proxy)
 }
@@ -300,3 +295,39 @@ func updateAddressLabels(agentConfig *daemonconfig.Agent, nodeLabels map[string]
 	result = labels.Merge(nodeLabels, result)
 	return result, !equality.Semantic.DeepEqual(nodeLabels, result)
 }
+
+// setupTunnelAndRunAgent should start the setup tunnel before starting kubelet and kubeproxy
+// there are special case for etcd agents, it will wait until it can find the apiaddress from
+// the address channel and update the proxy with the servers addresses, if in rke2 we need to
+// start the agent before the tunnel is setup to allow kubelet to start first and start the pods
+func setupTunnelAndRunAgent(ctx context.Context, nodeConfig *daemonconfig.Node, cfg cmds.Agent, proxy proxy.Proxy) error {
+	var agentRan bool
+	if cfg.ETCDAgent {
+		// only in rke2 run the agent before the tunnel setup and check for that later in the function
+		if proxy.IsAPIServerLBEnabled() {
+			if err := agent.Agent(&nodeConfig.AgentConfig); err != nil {
+				return err
+			}
+			agentRan = true
+		}
+		select {
+		case address := <-cfg.APIAddressCh:
+			cfg.ServerURL = address
+			u, err := url.Parse(cfg.ServerURL)
+			if err != nil {
+				logrus.Warn(err)
+			}
+			proxy.Update([]string{fmt.Sprintf("%s:%d", u.Hostname(), nodeConfig.ServerHTTPSPort)})
+		case <-ctx.Done():
+			return ctx.Err()
+		}
+	}
+
+	if err := tunnel.Setup(ctx, nodeConfig, proxy); err != nil {
+		return err
+	}
+	if !agentRan {
+		return agent.Agent(&nodeConfig.AgentConfig)
+	}
+	return nil
+}

pkg/agent/tunnel/tunnel.go

@@ -75,7 +75,10 @@ func Setup(ctx context.Context, config *config.Node, proxy proxy.Proxy) error {
 
 	endpoint, _ := client.CoreV1().Endpoints("default").Get(ctx, "kubernetes", metav1.GetOptions{})
 	if endpoint != nil {
-		proxy.Update(getAddresses(endpoint))
+		addresses := getAddresses(endpoint)
+		if len(addresses) > 0 {
+			proxy.Update(getAddresses(endpoint))
+		}
 	}
 
 	disconnect := map[string]context.CancelFunc{}

pkg/apiaddresses/controller.go

+package apiaddresses
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"net"
+	"strconv"
+
+	"github.com/rancher/k3s/pkg/daemons/config"
+	"github.com/rancher/k3s/pkg/etcd"
+	"github.com/rancher/k3s/pkg/version"
+	controllerv1 "github.com/rancher/wrangler-api/pkg/generated/controllers/core/v1"
+	etcdv3 "go.etcd.io/etcd/clientv3"
+	v1 "k8s.io/api/core/v1"
+)
+
+type EndpointsControllerGetter func() controllerv1.EndpointsController
+
+func Register(ctx context.Context, runtime *config.ControlRuntime, endpoints controllerv1.EndpointsController) error {
+	h := &handler{
+		endpointsController: endpoints,
+		runtime:             runtime,
+		ctx:                 ctx,
+	}
+	endpoints.OnChange(ctx, version.Program+"-apiserver-lb-controller", h.sync)
+
+	cl, err := etcd.GetClient(h.ctx, h.runtime, "https://127.0.0.1:2379")
+	if err != nil {
+		return err
+	}
+
+	h.etcdClient = cl
+
+	return nil
+}
+
+type handler struct {
+	endpointsController controllerv1.EndpointsController
+	runtime             *config.ControlRuntime
+	ctx                 context.Context
+	etcdClient          *etcdv3.Client
+}
+
+// This controller will update the version.program/apiaddresses etcd key with a list of
+// api addresses endpoints found in the kubernetes service in the default namespace
+func (h *handler) sync(key string, endpoint *v1.Endpoints) (*v1.Endpoints, error) {
+	if endpoint == nil {
+		return nil, nil
+	}
+
+	if endpoint.Namespace != "default" && endpoint.Name != "kubernetes" {
+		return nil, nil
+	}
+
+	w := &bytes.Buffer{}
+	if err := json.NewEncoder(w).Encode(getAddresses(endpoint)); err != nil {
+		return nil, err
+	}
+
+	_, err := h.etcdClient.Put(h.ctx, etcd.AddressKey, w.String())
+	if err != nil {
+		return nil, err
+	}
+
+	return endpoint, nil
+}
+
+func getAddresses(endpoint *v1.Endpoints) []string {
+	serverAddresses := []string{}
+	if endpoint == nil {
+		return serverAddresses
+	}
+	for _, subset := range endpoint.Subsets {
+		var port string
+		if len(subset.Ports) > 0 {
+			port = strconv.Itoa(int(subset.Ports[0].Port))
+		}
+		if port == "" {
+			port = "443"
+		}
+		for _, address := range subset.Addresses {
+			serverAddresses = append(serverAddresses, net.JoinHostPort(address.IP, port))
+		}
+	}
+	return serverAddresses
+}

pkg/cli/cmds/agent.go

@@ -14,7 +14,10 @@ type Agent struct {
 	TokenFile                string
 	ClusterSecret            string
 	ServerURL                string
+	APIAddressCh             chan string
 	DisableLoadBalancer      bool
+	ETCDAgent                bool
+	LBServerPort             int
 	ResolvConf               string
 	DataDir                  string
 	NodeIP                   string
@@ -155,6 +158,14 @@ var (
 		Destination: &AgentConfig.EnableSELinux,
 		EnvVar:      version.ProgramUpper + "_SELINUX",
 	}
+	LBServerPort = cli.IntFlag{
+		Name:        "lb-server-port",
+		Usage:       "(agent/node) Internal Loadbalancer port",
+		Hidden:      false,
+		Destination: &AgentConfig.LBServerPort,
+		EnvVar:      version.ProgramUpper + "_LB_SERVER_PORT",
+		Value:       0,
+	}
 )
 
 func CheckSELinuxFlags(ctx *cli.Context) error {

pkg/cli/cmds/etcd.go

-// +build !no_etcd
-
-package cmds
-
-const (
-	hideClusterFlags = false
-)

pkg/cli/cmds/server.go

@@ -10,6 +10,7 @@ import (
 const (
 	defaultSnapshotRentention    = 5
 	defaultSnapshotIntervalHours = 12
+	hideClusterFlags             = true
 )
 
 type Server struct {
@@ -54,6 +55,9 @@ type Server struct {
 	DisableCCM               bool
 	DisableNPC               bool
 	DisableKubeProxy         bool
+	DisableAPIServer         bool
+	DisableControllerManager bool
+	DisableETCD              bool
 	ClusterInit              bool
 	ClusterReset             bool
 	ClusterResetRestorePath  string
@@ -280,6 +284,21 @@ func NewServerCommand(action func(*cli.Context) error) cli.Command {
 				Usage:       "(components) Disable " + version.Program + " default network policy controller",
 				Destination: &ServerConfig.DisableNPC,
 			},
+			cli.BoolFlag{
+				Name:        "disable-api-server",
+				Usage:       "(components) Disable running api server",
+				Destination: &ServerConfig.DisableAPIServer,
+			},
+			cli.BoolFlag{
+				Name:        "disable-controller-manager",
+				Usage:       "(components) Disable running kube-controller-manager",
+				Destination: &ServerConfig.DisableControllerManager,
+			},
+			cli.BoolFlag{
+				Name:        "disable-etcd",
+				Usage:       "(components) Disable running etcd",
+				Destination: &ServerConfig.DisableETCD,
+			},
 			NodeNameFlag,
 			WithNodeIDFlag,
 			NodeLabels,

pkg/cli/server/server.go

@@ -7,6 +7,7 @@ import (
 	"os"
 	"path/filepath"
 	"strings"
+	"time"
 
 	systemd "github.com/coreos/go-systemd/daemon"
 	"github.com/erikdubbelboer/gspt"
@@ -14,6 +15,7 @@ import (
 	"github.com/rancher/k3s/pkg/agent"
 	"github.com/rancher/k3s/pkg/cli/cmds"
 	"github.com/rancher/k3s/pkg/datadir"
+	"github.com/rancher/k3s/pkg/etcd"
 	"github.com/rancher/k3s/pkg/netutil"
 	"github.com/rancher/k3s/pkg/rootless"
 	"github.com/rancher/k3s/pkg/server"
@@ -31,6 +33,10 @@ import (
 	_ "github.com/mattn/go-sqlite3"    // ensure we have sqlite
 )
 
+const (
+	lbServerPort = 6444
+)
+
 func Run(app *cli.Context) error {
 	if err := cmds.InitLogging(); err != nil {
 		return err
@@ -86,7 +92,6 @@ func run(app *cli.Context, cfg *cmds.Server) error {
 	serverConfig.ControlConfig.DataDir = cfg.DataDir
 	serverConfig.ControlConfig.KubeConfigOutput = cfg.KubeConfigOutput
 	serverConfig.ControlConfig.KubeConfigMode = cfg.KubeConfigMode
-	serverConfig.ControlConfig.NoScheduler = cfg.DisableScheduler
 	serverConfig.Rootless = cfg.Rootless
 	serverConfig.ControlConfig.SANs = knownIPs(cfg.TLSSan)
 	serverConfig.ControlConfig.BindAddress = cfg.BindAddress
@@ -109,6 +114,10 @@ func run(app *cli.Context, cfg *cmds.Server) error {
 	serverConfig.ControlConfig.DisableCCM = cfg.DisableCCM
 	serverConfig.ControlConfig.DisableNPC = cfg.DisableNPC
 	serverConfig.ControlConfig.DisableKubeProxy = cfg.DisableKubeProxy
+	serverConfig.ControlConfig.DisableETCD = cfg.DisableETCD
+	serverConfig.ControlConfig.DisableAPIServer = cfg.DisableAPIServer
+	serverConfig.ControlConfig.DisableScheduler = cfg.DisableScheduler
+	serverConfig.ControlConfig.DisableControllerManager = cfg.DisableControllerManager
 	serverConfig.ControlConfig.ClusterInit = cfg.ClusterInit
 	serverConfig.ControlConfig.EncryptSecrets = cfg.EncryptSecrets
 	serverConfig.ControlConfig.EtcdSnapshotName = cfg.EtcdSnapshotName
@@ -119,7 +128,7 @@ func run(app *cli.Context, cfg *cmds.Server) error {
 	serverConfig.ControlConfig.EtcdExposeMetrics = cfg.EtcdExposeMetrics
 
 	if cfg.ClusterResetRestorePath != "" && !cfg.ClusterReset {
-		return errors.New("Invalid flag use. --cluster-reset required with --cluster-reset-restore-path")
+		return errors.New("invalid flag use. --cluster-reset required with --cluster-reset-restore-path")
 	}
 
 	serverConfig.ControlConfig.ClusterReset = cfg.ClusterReset
@@ -129,6 +138,13 @@ func run(app *cli.Context, cfg *cmds.Server) error {
 		serverConfig.ControlConfig.SupervisorPort = serverConfig.ControlConfig.HTTPSPort
 	}
 
+	if serverConfig.ControlConfig.DisableAPIServer {
+		serverConfig.ControlConfig.APIServerPort = lbServerPort
+		if serverConfig.ControlConfig.SupervisorPort != serverConfig.ControlConfig.HTTPSPort {
+			serverConfig.ControlConfig.APIServerPort = lbServerPort + 1
+		}
+	}
+
 	if cmds.AgentConfig.FlannelIface != "" && cmds.AgentConfig.NodeIP == "" {
 		cmds.AgentConfig.NodeIP = netutil.GetIPFromInterface(cmds.AgentConfig.FlannelIface)
 	}
@@ -245,6 +261,7 @@ func run(app *cli.Context, cfg *cmds.Server) error {
 	os.Unsetenv("NOTIFY_SOCKET")
 
 	ctx := signals.SetupSignalHandler(context.Background())
+
 	if err := server.StartServer(ctx, &serverConfig); err != nil {
 		return err
 	}
@@ -280,13 +297,24 @@ func run(app *cli.Context, cfg *cmds.Server) error {
 	agentConfig.DataDir = filepath.Dir(serverConfig.ControlConfig.DataDir)
 	agentConfig.ServerURL = url
 	agentConfig.Token = token
-	agentConfig.DisableLoadBalancer = true
+	agentConfig.DisableLoadBalancer = !serverConfig.ControlConfig.DisableAPIServer
+	agentConfig.ETCDAgent = serverConfig.ControlConfig.DisableAPIServer
+
 	agentConfig.Rootless = cfg.Rootless
+
 	if agentConfig.Rootless {
 		// let agent specify Rootless kubelet flags, but not unshare twice
 		agentConfig.RootlessAlreadyUnshared = true
 	}
 
+	if serverConfig.ControlConfig.DisableAPIServer {
+		// setting LBServerPort to a prespecified port to initialize the kubeconfigs with the right address
+		agentConfig.LBServerPort = lbServerPort
+		// initialize the apiAddress Channel for receiving the api address from etcd
+		agentConfig.APIAddressCh = make(chan string, 1)
+		setAPIAddressChannel(ctx, &serverConfig, &agentConfig)
+		defer close(agentConfig.APIAddressCh)
+	}
 	return agent.Run(ctx, agentConfig)
 }
 
@@ -311,3 +339,30 @@ func getArgValueFromList(searchArg string, argList []string) string {
 	}
 	return value
 }
+
+// setAPIAddressChannel will try to get the api address key from etcd and when it succeed it will
+// set the APIAddressCh channel with its value, the function works for both k3s and rke2 in case
+// of k3s we block returning back to the agent.Run until we get the api address, however in rke2
+// the code will not block operation and will run the operation in a goroutine
+func setAPIAddressChannel(ctx context.Context, serverConfig *server.Config, agentConfig *cmds.Agent) {
+	// start a goroutine to check for the server ip if set from etcd in case of rke2
+	if serverConfig.ControlConfig.HTTPSPort != serverConfig.ControlConfig.SupervisorPort {
+		go getAPIAddressFromEtcd(ctx, serverConfig, agentConfig)
+		return
+	}
+	getAPIAddressFromEtcd(ctx, serverConfig, agentConfig)
+}
+
+func getAPIAddressFromEtcd(ctx context.Context, serverConfig *server.Config, agentConfig *cmds.Agent) {
+	t := time.NewTicker(5 * time.Second)
+	defer t.Stop()
+	for range t.C {
+		serverAddress, err := etcd.GetAPIServerURLFromETCD(ctx, &serverConfig.ControlConfig)
+		if err == nil {
+			agentConfig.ServerURL = "https://" + serverAddress
+			agentConfig.APIAddressCh <- agentConfig.ServerURL
+			break
+		}
+		logrus.Warn(err)
+	}
+}

pkg/cluster/cluster.go

@@ -2,6 +2,7 @@ package cluster
 
 import (
 	"context"
+	"net/url"
 	"strings"
 
 	"github.com/k3s-io/kine/pkg/client"
@@ -10,6 +11,7 @@ import (
 	"github.com/rancher/k3s/pkg/clientaccess"
 	"github.com/rancher/k3s/pkg/cluster/managed"
 	"github.com/rancher/k3s/pkg/daemons/config"
+	"github.com/rancher/k3s/pkg/etcd"
 )
 
 type Cluster struct {
@@ -34,6 +36,31 @@ func (c *Cluster) Start(ctx context.Context) (<-chan struct{}, error) {
 		return nil, errors.Wrap(err, "init cluster datastore and https")
 	}
 
+	if c.config.DisableETCD {
+		ready := make(chan struct{})
+		defer close(ready)
+
+		// try to get /db/info urls first before attempting to use join url
+		clientURLs, _, err := etcd.ClientURLs(ctx, c.clientAccessInfo)
+		if err != nil {
+			return nil, err
+		}
+		if len(clientURLs) < 1 {
+			clientURL, err := url.Parse(c.config.JoinURL)
+			if err != nil {
+				return nil, err
+			}
+			clientURL.Host = clientURL.Hostname() + ":2379"
+			clientURLs = append(clientURLs, clientURL.String())
+		}
+		etcdProxy, err := etcd.NewETCDProxy(true, c.config.DataDir, clientURLs[0])
+		if err != nil {
+			return nil, err
+		}
+		c.setupEtcdProxy(ctx, etcdProxy)
+		return ready, nil
+	}
+
 	// start managed database (if necessary)
 	if err := c.start(ctx); err != nil {
 		return nil, errors.Wrap(err, "start managed database")

pkg/cluster/managed.go

@@ -126,3 +126,23 @@ func (c *Cluster) assignManagedDriver(ctx context.Context) error {
 
 	return nil
 }
+
+// setupEtcdProxy
+func (c *Cluster) setupEtcdProxy(ctx context.Context, etcdProxy etcd.Proxy) {
+	if c.managedDB == nil {
+		return
+	}
+	go func() {
+		t := time.NewTicker(30 * time.Second)
+		defer t.Stop()
+		for range t.C {
+			newAddresses, err := c.managedDB.GetMembersClientURLs(ctx)
+			if err != nil {
+				logrus.Warnf("failed to get etcd client URLs: %v", err)
+				continue
+			}
+			etcdProxy.Update(newAddresses)
+
+		}
+	}()
+}

pkg/cluster/managed/drivers.go

@@ -22,6 +22,7 @@ type Driver interface {
 	Restore(ctx context.Context) error
 	EndpointName() string
 	Snapshot(ctx context.Context, config *config.Control) error
+	GetMembersClientURLs(ctx context.Context) ([]string, error)
 }
 
 func RegisterDriver(d Driver) {

pkg/daemons/agent/agent.go

@@ -30,7 +30,6 @@ func Agent(config *config.Agent) error {
 
 	logs.InitLogs()
 	defer logs.FlushLogs()
-
 	if err := startKubelet(config); err != nil {
 		return err
 	}

pkg/daemons/config/types.go

@@ -38,6 +38,7 @@ type Node struct {
 	AgentConfig              Agent
 	CACerts                  []byte
 	Certificate              *tls.Certificate
+	ServerHTTPSPort          int
 }
 
 type Containerd struct {
@@ -115,7 +116,6 @@ type Control struct {
 	Skips                    map[string]bool
 	Disables                 map[string]bool
 	Datastore                endpoint.Config
-	NoScheduler              bool
 	ExtraAPIArgs             []string
 	ExtraControllerArgs      []string
 	ExtraCloudControllerArgs []string
@@ -128,6 +128,10 @@ type Control struct {
 	DisableCCM               bool
 	DisableNPC               bool
 	DisableKubeProxy         bool
+	DisableAPIServer         bool
+	DisableControllerManager bool
+	DisableScheduler         bool
+	DisableETCD              bool
 	ClusterInit              bool
 	ClusterReset             bool
 	ClusterResetRestorePath  string

pkg/daemons/control/server.go

@@ -95,15 +95,20 @@ func Server(ctx context.Context, cfg *config.Control) error {
 	cfg.Runtime.Tunnel = setupTunnel()
 	util.DisableProxyHostnameCheck = true
 
-	auth, handler, err := apiServer(ctx, cfg, runtime)
-	if err != nil {
-		return err
-	}
+	var auth authenticator.Request
+	var handler http.Handler
+	var err error
 
-	if err := waitForAPIServerInBackground(ctx, runtime); err != nil {
-		return err
-	}
+	if !cfg.DisableAPIServer {
+		auth, handler, err = apiServer(ctx, cfg, runtime)
+		if err != nil {
+			return err
+		}
 
+		if err := waitForAPIServerInBackground(ctx, runtime); err != nil {
+			return err
+		}
+	}
 	basicAuth, err := basicAuthenticator(runtime.PasswdFile)
 	if err != nil {
 		return err
@@ -112,14 +117,15 @@ func Server(ctx context.Context, cfg *config.Control) error {
 	runtime.Authenticator = combineAuthenticators(basicAuth, auth)
 	runtime.Handler = handler
 
-	if !cfg.NoScheduler {
+	if !cfg.DisableScheduler {
 		if err := scheduler(cfg, runtime); err != nil {
 			return err
 		}
 	}
-
-	if err := controllerManager(cfg, runtime); err != nil {
-		return err
+	if !cfg.DisableControllerManager {
+		if err := controllerManager(cfg, runtime); err != nil {
+			return err
+		}
 	}
 
 	if !cfg.DisableCCM {
@@ -976,7 +982,7 @@ func cloudControllerManager(ctx context.Context, cfg *config.Control, runtime *c
 				select {
 				case <-ctx.Done():
 					logrus.Fatalf("cloud-controller-manager context canceled: %v", ctx.Err())
-				case <-time.After(time.Second):
+				case <-time.After(5 * time.Second):
 					continue
 				}
 			}

pkg/etcd/controller.go

@@ -11,8 +11,8 @@ import (
 )
 
 const (
-	nodeID       = "etcd.k3s.cattle.io/node-name"
-	nodeAddress  = "etcd.k3s.cattle.io/node-address"
+	NodeID       = "etcd.k3s.cattle.io/node-name"
+	NodeAddress  = "etcd.k3s.cattle.io/node-address"
 	master       = "node-role.kubernetes.io/master"
 	controlPlane = "node-role.kubernetes.io/control-plane"
 	etcdRole     = "node-role.kubernetes.io/etcd"
@@ -56,10 +56,11 @@ func (h *handler) sync(key string, node *v1.Node) (*v1.Node, error) {
 }
 
 func (h *handler) handleSelf(node *v1.Node) (*v1.Node, error) {
-	if node.Annotations[nodeID] == h.etcd.name &&
-		node.Annotations[nodeAddress] == h.etcd.address &&
+	if node.Annotations[NodeID] == h.etcd.name &&
+		node.Annotations[NodeAddress] == h.etcd.address &&
 		node.Labels[etcdRole] == "true" &&
-		node.Labels[controlPlane] == "true" {
+		node.Labels[controlPlane] == "true" ||
+		h.etcd.config.DisableETCD {
 		return node, nil
 	}
 
@@ -67,8 +68,8 @@ func (h *handler) handleSelf(node *v1.Node) (*v1.Node, error) {
 	if node.Annotations == nil {
 		node.Annotations = map[string]string{}
 	}
-	node.Annotations[nodeID] = h.etcd.name
-	node.Annotations[nodeAddress] = h.etcd.address
+	node.Annotations[NodeID] = h.etcd.name
+	node.Annotations[NodeAddress] = h.etcd.address
 	node.Labels[etcdRole] = "true"
 	node.Labels[master] = "true"
 	node.Labels[controlPlane] = "true"
@@ -81,11 +82,10 @@ func (h *handler) onRemove(key string, node *v1.Node) (*v1.Node, error) {
 		return node, nil
 	}
 
-	id := node.Annotations[nodeID]
-	address := node.Annotations[nodeAddress]
-	if address == "" {
+	id := node.Annotations[NodeID]
+	address, ok := node.Annotations[NodeAddress]
+	if !ok {
 		return node, nil
 	}
-
 	return node, h.etcd.removePeer(h.ctx, id, address)
 }

pkg/etcd/etcd.go

@@ -58,14 +58,18 @@ func NewETCD() *ETCD {
 	}
 }
 
-var learnerProgressKey = version.Program + "/etcd/learnerProgress"
+var (
+	learnerProgressKey = version.Program + "/etcd/learnerProgress"
+	// AddressKey will contain the value of api addresses list
+	AddressKey = version.Program + "/apiaddresses"
+)
 
 const (
 	snapshotPrefix      = "etcd-snapshot-"
 	endpoint            = "https://127.0.0.1:2379"
 	testTimeout         = time.Second * 10
 	manageTickerTime    = time.Second * 15
-	learnerMaxStallTime = time.Minute * 1
+	learnerMaxStallTime = time.Minute * 5
 
 	// defaultDialTimeout is intentionally short so that connections timeout within the testTimeout defined above
 	defaultDialTimeout = 2 * time.Second
@@ -206,11 +210,6 @@ func (e *ETCD) Start(ctx context.Context, clientAccessInfo *clientaccess.Info) e
 		return errors.Wrapf(err, "configuration validation failed")
 	}
 
-	e.config.Runtime.ClusterControllerStart = func(ctx context.Context) error {
-		Register(ctx, e, e.config.Runtime.Core.Core().V1().Node())
-		return nil
-	}
-
 	if !e.config.EtcdDisableSnapshots {
 		e.setSnapshotFunction(ctx)
 		e.cron.Start()
@@ -246,12 +245,12 @@ func (e *ETCD) Start(ctx context.Context, clientAccessInfo *clientaccess.Info) e
 
 // join attempts to add a member to an existing cluster
 func (e *ETCD) join(ctx context.Context, clientAccessInfo *clientaccess.Info) error {
-	clientURLs, memberList, err := e.clientURLs(ctx, clientAccessInfo)
+	clientURLs, memberList, err := ClientURLs(ctx, clientAccessInfo)
 	if err != nil {
 		return err
 	}
 
-	client, err := getClient(ctx, e.runtime, clientURLs...)
+	client, err := GetClient(ctx, e.runtime, clientURLs...)
 	if err != nil {
 		return err
 	}
@@ -316,13 +315,13 @@ func (e *ETCD) Register(ctx context.Context, config *config.Control, handler htt
 	e.config = config
 	e.runtime = config.Runtime
 
-	client, err := getClient(ctx, e.runtime, endpoint)
+	client, err := GetClient(ctx, e.runtime, endpoint)
 	if err != nil {
 		return nil, err
 	}
 	e.client = client
 
-	address, err := getAdvertiseAddress(config.PrivateIP)
+	address, err := GetAdvertiseAddress(config.PrivateIP)
 	if err != nil {
 		return nil, err
 	}
@@ -335,6 +334,10 @@ func (e *ETCD) Register(ctx context.Context, config *config.Control, handler htt
 	if err := e.setName(false); err != nil {
 		return nil, err
 	}
+	e.config.Runtime.ClusterControllerStart = func(ctx context.Context) error {
+		Register(ctx, e, e.config.Runtime.Core.Core().V1().Node())
+		return nil
+	}
 
 	tombstoneFile := filepath.Join(etcdDBDir(e.config), "tombstone")
 	if _, err := os.Stat(tombstoneFile); err == nil {
@@ -405,7 +408,7 @@ func (e *ETCD) infoHandler() http.Handler {
 }
 
 // getClient returns an etcd client connected to the specified endpoints
-func getClient(ctx context.Context, runtime *config.ControlRuntime, endpoints ...string) (*etcd.Client, error) {
+func GetClient(ctx context.Context, runtime *config.ControlRuntime, endpoints ...string) (*etcd.Client, error) {
 	cfg, err := getClientConfig(ctx, runtime, endpoints...)
 	if err != nil {
 		return nil, err
@@ -450,7 +453,7 @@ func toTLSConfig(runtime *config.ControlRuntime) (*tls.Config, error) {
 }
 
 // getAdvertiseAddress returns the IP address best suited for advertising to clients
-func getAdvertiseAddress(advertiseIP string) (string, error) {
+func GetAdvertiseAddress(advertiseIP string) (string, error) {
 	ip := advertiseIP
 	if ip == "" {
 		ipAddr, err := utilnet.ChooseHostInterface()
@@ -684,7 +687,7 @@ func (e *ETCD) setLearnerProgress(ctx context.Context, status *learnerProgress)
 }
 
 // clientURLs returns a list of all non-learner etcd cluster member client access URLs
-func (e *ETCD) clientURLs(ctx context.Context, clientAccessInfo *clientaccess.Info) ([]string, Members, error) {
+func ClientURLs(ctx context.Context, clientAccessInfo *clientaccess.Info) ([]string, Members, error) {
 	var memberList Members
 	resp, err := clientaccess.Get("/db/info", clientAccessInfo)
 	if err != nil {
@@ -737,7 +740,7 @@ func (e *ETCD) preSnapshotSetup(ctx context.Context, config *config.Control) err
 		if e.config == nil {
 			e.config = config
 		}
-		client, err := getClient(ctx, e.config.Runtime, endpoint)
+		client, err := GetClient(ctx, e.config.Runtime, endpoint)
 		if err != nil {
 			return err
 		}
@@ -892,3 +895,49 @@ func backupDirWithRetention(dir string, maxBackupRetention int) (string, error)
 	}
 	return backupDir, nil
 }
+
+// GetAPIServerURLFromETCD will try to fetch the version.Program/apiaddresses key from etcd
+// when it succeed it will parse the first address in the list and return back an address
+func GetAPIServerURLFromETCD(ctx context.Context, cfg *config.Control) (string, error) {
+	if cfg.Runtime == nil {
+		return "", fmt.Errorf("runtime is not ready yet")
+	}
+	cl, err := GetClient(ctx, cfg.Runtime, endpoint)
+	if err != nil {
+		return "", err
+	}
+	etcdResp, err := cl.KV.Get(ctx, AddressKey)
+	if err != nil {
+		return "", err
+	}
+
+	if etcdResp.Count < 1 {
+		return "", fmt.Errorf("servers addresses are not yet set")
+	}
+	var addresses []string
+	if err := json.Unmarshal(etcdResp.Kvs[0].Value, &addresses); err != nil {
+		return "", fmt.Errorf("failed to unmarshal etcd key: %v", err)
+	}
+
+	return addresses[0], nil
+}
+
+// GetMembersClientURLs will list through the member lists in etcd and return
+// back a combined list of client urls for each member in the cluster
+func (e *ETCD) GetMembersClientURLs(ctx context.Context) ([]string, error) {
+	ctx, cancel := context.WithTimeout(ctx, testTimeout)
+	defer cancel()
+
+	members, err := e.client.MemberList(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	var memberUrls []string
+	for _, member := range members.Members {
+		for _, clientURL := range member.ClientURLs {
+			memberUrls = append(memberUrls, string(clientURL))
+		}
+	}
+	return memberUrls, nil
+}

pkg/etcd/etcdproxy.go

+package etcd
+
+import (
+	"net/url"
+
+	"github.com/pkg/errors"
+	"github.com/rancher/k3s/pkg/agent/loadbalancer"
+)
+
+type Proxy interface {
+	Update(addresses []string)
+	ETCDURL() string
+	ETCDAddresses() []string
+	ETCDServerURL() string
+}
+
+// NewETCDProxy initializes a new proxy structure that contain a load balancer
+// which listens on port 2379 and proxy between etcd cluster members
+func NewETCDProxy(enabled bool, dataDir, etcdURL string) (Proxy, error) {
+	e := &etcdproxy{
+		dataDir:        dataDir,
+		initialETCDURL: etcdURL,
+		etcdURL:        etcdURL,
+	}
+
+	if enabled {
+		lb, err := loadbalancer.New(dataDir, loadbalancer.ETCDServerServiceName, etcdURL, 2379)
+		if err != nil {
+			return nil, err
+		}
+		e.etcdLB = lb
+		e.etcdLBURL = lb.LoadBalancerServerURL()
+	}
+
+	u, err := url.Parse(e.initialETCDURL)
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to parse etcd client URL")
+	}
+	e.fallbackETCDAddress = u.Host
+	e.etcdPort = u.Port()
+
+	return e, nil
+}
+
+type etcdproxy struct {
+	dataDir   string
+	etcdLBURL string
+
+	initialETCDURL      string
+	etcdURL             string
+	etcdPort            string
+	fallbackETCDAddress string
+	etcdAddresses       []string
+	etcdLB              *loadbalancer.LoadBalancer
+}
+
+func (e *etcdproxy) Update(addresses []string) {
+	if e.etcdLB != nil {
+		e.etcdLB.Update(addresses)
+	}
+}
+
+func (e *etcdproxy) ETCDURL() string {
+	return e.etcdURL
+}
+
+func (e *etcdproxy) ETCDAddresses() []string {
+	if len(e.etcdAddresses) > 0 {
+		return e.etcdAddresses
+	}
+	return []string{e.fallbackETCDAddress}
+}
+
+func (e *etcdproxy) ETCDServerURL() string {
+	return e.etcdURL
+}

pkg/server/etcd.go

+package server
+
+import (
+	"context"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"time"
+
+	"github.com/rancher/k3s/pkg/etcd"
+	"github.com/sirupsen/logrus"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+// setETCDLabelsAndAnnotations will set the etcd role label if not exists also it
+// sets special annotaitons on the node object which are etcd node id and etcd node
+// address, the function will also remove the controlplane and master role labels if
+// they exist on the node
+func setETCDLabelsAndAnnotations(ctx context.Context, config *Config) error {
+	t := time.NewTicker(5 * time.Second)
+	defer t.Stop()
+	for range t.C {
+		controlConfig := &config.ControlConfig
+
+		sc, err := newContext(ctx, controlConfig.Runtime.KubeConfigAdmin)
+		if err != nil {
+			logrus.Infof("Failed to set etcd role label: %v", err)
+			continue
+		}
+
+		if err := stageFiles(ctx, sc, controlConfig); err != nil {
+			logrus.Infof("Failed to set etcd role label: %v", err)
+			continue
+		}
+
+		if err := sc.Start(ctx); err != nil {
+			logrus.Infof("Failed to set etcd role label: %v", err)
+			continue
+		}
+
+		controlConfig.Runtime.Core = sc.Core
+		nodes := sc.Core.Core().V1().Node()
+
+		nodeName := os.Getenv("NODE_NAME")
+		if nodeName == "" {
+			logrus.Info("Failed to set etcd role label: node name not set")
+			continue
+		}
+		node, err := nodes.Get(nodeName, metav1.GetOptions{})
+		if err != nil {
+			logrus.Infof("Failed to set etcd role label: %v", err)
+			continue
+		}
+
+		if node.Labels == nil {
+			node.Labels = make(map[string]string)
+		}
+
+		// remove controlplane label if role label exists
+		var controlRoleLabelExists bool
+		if _, ok := node.Labels[MasterRoleLabelKey]; ok {
+			delete(node.Labels, MasterRoleLabelKey)
+			controlRoleLabelExists = true
+		}
+		if _, ok := node.Labels[ControlPlaneRoleLabelKey]; ok {
+			delete(node.Labels, ControlPlaneRoleLabelKey)
+			controlRoleLabelExists = true
+		}
+
+		if v, ok := node.Labels[ETCDRoleLabelKey]; ok && v == "true" && !controlRoleLabelExists {
+			break
+		}
+
+		node.Labels[ETCDRoleLabelKey] = "true"
+
+		// this is replacement to the etcd controller handleself function
+		if node.Annotations == nil {
+			node.Annotations = map[string]string{}
+		}
+		fileName := filepath.Join(controlConfig.DataDir, "db", "etcd", "name")
+
+		data, err := ioutil.ReadFile(fileName)
+		if err != nil {
+			logrus.Infof("Waiting for etcd node name file to be available: %v", err)
+			continue
+		}
+		etcdNodeName := string(data)
+		node.Annotations[etcd.NodeID] = etcdNodeName
+
+		address, err := etcd.GetAdvertiseAddress(controlConfig.PrivateIP)
+		if err != nil {
+			logrus.Infof("Waiting for etcd node address to be available: %v", err)
+			continue
+		}
+		node.Annotations[etcd.NodeAddress] = address
+
+		_, err = nodes.Update(node)
+		if err == nil {
+			logrus.Infof("Successfully set etcd role label and annotations on node %s", nodeName)
+			break
+		}
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		}
+	}
+	return nil
+}

pkg/server/server.go

@@ -17,6 +17,7 @@ import (
 
 	"github.com/k3s-io/helm-controller/pkg/helm"
 	"github.com/pkg/errors"
+	"github.com/rancher/k3s/pkg/apiaddresses"
 	"github.com/rancher/k3s/pkg/clientaccess"
 	"github.com/rancher/k3s/pkg/daemons/config"
 	"github.com/rancher/k3s/pkg/daemons/control"
@@ -40,6 +41,7 @@ import (
 const (
 	MasterRoleLabelKey       = "node-role.kubernetes.io/master"
 	ControlPlaneRoleLabelKey = "node-role.kubernetes.io/control-plane"
+	ETCDRoleLabelKey         = "node-role.kubernetes.io/etcd"
 )
 
 func ResolveDataDir(dataDir string) (string, error) {
@@ -62,7 +64,11 @@ func StartServer(ctx context.Context, config *Config) error {
 
 	config.ControlConfig.Runtime.Handler = router(ctx, config)
 
-	go startOnAPIServerReady(ctx, config)
+	if config.ControlConfig.DisableAPIServer {
+		go setETCDLabelsAndAnnotations(ctx, config)
+	} else {
+		go startOnAPIServerReady(ctx, config)
+	}
 
 	for _, hook := range config.StartupHooks {
 		if err := hook(ctx, config.ControlConfig.Runtime.APIServerReady, config.ControlConfig.Runtime.KubeConfigAdmin); err != nil {
@@ -137,9 +143,8 @@ func runControllers(ctx context.Context, config *Config) error {
 			panic(err)
 		}
 	}
-	if !config.DisableAgent {
-		go setControlPlaneRoleLabel(ctx, sc.Core.Core().V1().Node())
-	}
+
+	go setControlPlaneRoleLabel(ctx, sc.Core.Core().V1().Node(), config)
 
 	go setClusterDNSConfig(ctx, config, sc.Core.Core().V1().ConfigMap())
 
@@ -185,6 +190,10 @@ func coreControllers(ctx context.Context, sc *Context, config *Config) error {
 		return err
 	}
 
+	if err := apiaddresses.Register(ctx, config.ControlConfig.Runtime, sc.Core.Core().V1().Endpoints()); err != nil {
+		return err
+	}
+
 	if config.Rootless {
 		return rootlessports.Register(ctx, sc.Core.Core().V1().Service(), !config.DisableServiceLB, config.ControlConfig.HTTPSPort)
 	}
@@ -420,7 +429,10 @@ func isSymlink(config string) bool {
 	return false
 }
 
-func setControlPlaneRoleLabel(ctx context.Context, nodes v1.NodeClient) error {
+func setControlPlaneRoleLabel(ctx context.Context, nodes v1.NodeClient, config *Config) error {
+	if config.DisableAgent || config.ControlConfig.DisableAPIServer {
+		return nil
+	}
 	for {
 		nodeName := os.Getenv("NODE_NAME")
 		if nodeName == "" {
@@ -434,7 +446,15 @@ func setControlPlaneRoleLabel(ctx context.Context, nodes v1.NodeClient) error {
 			time.Sleep(1 * time.Second)
 			continue
 		}
-		if v, ok := node.Labels[ControlPlaneRoleLabelKey]; ok && v == "true" {
+		// remove etcd label if etcd is disabled
+		var etcdRoleLabelExists bool
+		if config.ControlConfig.DisableETCD {
+			if _, ok := node.Labels[ETCDRoleLabelKey]; ok {
+				delete(node.Labels, ETCDRoleLabelKey)
+				etcdRoleLabelExists = true
+			}
+		}
+		if v, ok := node.Labels[ControlPlaneRoleLabelKey]; ok && v == "true" && !etcdRoleLabelExists {
 			break
 		}
 		if node.Labels == nil {
@@ -442,6 +462,7 @@ func setControlPlaneRoleLabel(ctx context.Context, nodes v1.NodeClient) error {
 		}
 		node.Labels[ControlPlaneRoleLabelKey] = "true"
 		node.Labels[MasterRoleLabelKey] = "true"
+
 		_, err = nodes.Update(node)
 		if err == nil {
 			logrus.Infof("Control-plane role label has been set successfully on node: %s", nodeName)