Remove DynamicKubeletConfig from init and join workflow, also remove…

cmd/kubeadm/app/apis/kubeadm/validation/validation_test.go

@@ -682,10 +682,6 @@ func TestValidateFeatureGates(t *testing.T) {
 	}{
 		{featureFlag{"Unknown": true}, false},
 		{featureFlag{"Unknown": false}, false},
-		{featureFlag{"CoreDNS": true}, false},
-		{featureFlag{"CoreDNS": false}, false},
-		{featureFlag{"DynamicKubeletConfig": true}, true},
-		{featureFlag{"DynamicKubeletConfig": false}, true},
 	}
 	for _, rt := range tests {
 		actual := ValidateFeatureGates(rt.featureGates, nil)

cmd/kubeadm/app/cmd/init.go

@@ -48,12 +48,10 @@ import (
 	kubeconfigphase "k8s.io/kubernetes/cmd/kubeadm/app/phases/kubeconfig"
 	kubeletphase "k8s.io/kubernetes/cmd/kubeadm/app/phases/kubelet"
 	uploadconfigphase "k8s.io/kubernetes/cmd/kubeadm/app/phases/uploadconfig"
-	"k8s.io/kubernetes/cmd/kubeadm/app/preflight"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	"k8s.io/kubernetes/cmd/kubeadm/app/util/apiclient"
 	configutil "k8s.io/kubernetes/cmd/kubeadm/app/util/config"
 	kubeconfigutil "k8s.io/kubernetes/cmd/kubeadm/app/util/kubeconfig"
-	utilsexec "k8s.io/utils/exec"
 )
 
 var (
@@ -491,19 +489,6 @@ func runInit(i *initData, out io.Writer) error {
 		return errors.Wrap(err, "error creating kubelet configuration ConfigMap")
 	}
 
-	// This feature is disabled by default
-	if features.Enabled(i.cfg.FeatureGates, features.DynamicKubeletConfig) {
-		kubeletVersion, err := preflight.GetKubeletVersion(utilsexec.New())
-		if err != nil {
-			return err
-		}
-
-		// Enable dynamic kubelet configuration for the node.
-		if err := kubeletphase.EnableDynamicConfigForNode(client, i.cfg.NodeRegistration.Name, kubeletVersion); err != nil {
-			return errors.Wrap(err, "error enabling dynamic kubelet configuration")
-		}
-	}
-
 	klog.V(1).Infof("[init] ensuring DNS addon")
 	if err := dnsaddonphase.EnsureDNSAddon(i.cfg, client); err != nil {
 		return errors.Wrap(err, "error ensuring dns addon")

cmd/kubeadm/app/cmd/join.go

@@ -39,7 +39,6 @@ import (
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/validation"
 	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
 	"k8s.io/kubernetes/cmd/kubeadm/app/discovery"
-	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	certsphase "k8s.io/kubernetes/cmd/kubeadm/app/phases/certs"
 	controlplanephase "k8s.io/kubernetes/cmd/kubeadm/app/phases/controlplane"
 	etcdphase "k8s.io/kubernetes/cmd/kubeadm/app/phases/etcd"
@@ -536,13 +535,6 @@ func (j *Join) BootstrapKubelet(tlsBootstrapCfg *clientcmdapi.Config) error {
 		return errors.Wrap(err, "error uploading crisocket")
 	}
 
-	// This feature is disabled by default in kubeadm
-	if features.Enabled(j.initCfg.FeatureGates, features.DynamicKubeletConfig) {
-		if err := kubeletphase.EnableDynamicConfigForNode(client, j.cfg.NodeRegistration.Name, kubeletVersion); err != nil {
-			return errors.Wrap(err, "error consuming base kubelet configuration")
-		}
-	}
-
 	return nil
 }
 

cmd/kubeadm/app/features/features.go

@@ -41,8 +41,7 @@ var coreDNSMessage = "featureGates:CoreDNS has been removed in v1.13\n" +
 
 // InitFeatureGates are the default feature gates for the init command
 var InitFeatureGates = FeatureList{
-	CoreDNS:              {FeatureSpec: utilfeature.FeatureSpec{Default: true, PreRelease: utilfeature.Deprecated}, HiddenInHelpText: true, DeprecationMessage: coreDNSMessage},
-	DynamicKubeletConfig: {FeatureSpec: utilfeature.FeatureSpec{Default: false, PreRelease: utilfeature.Beta}},
+	CoreDNS: {FeatureSpec: utilfeature.FeatureSpec{Default: true, PreRelease: utilfeature.Deprecated}, HiddenInHelpText: true, DeprecationMessage: coreDNSMessage},
 }
 
 // Feature represents a feature being gated

cmd/kubeadm/app/phases/controlplane/BUILD

@@ -16,7 +16,6 @@ go_test(
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/constants:go_default_library",
-        "//cmd/kubeadm/app/features:go_default_library",
         "//cmd/kubeadm/app/phases/certs:go_default_library",
         "//cmd/kubeadm/test:go_default_library",
         "//pkg/kubeapiserver/authorizer/modes:go_default_library",
@@ -36,7 +35,6 @@ go_library(
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/constants:go_default_library",
-        "//cmd/kubeadm/app/features:go_default_library",
         "//cmd/kubeadm/app/images:go_default_library",
         "//cmd/kubeadm/app/phases/certs:go_default_library",
         "//cmd/kubeadm/app/util:go_default_library",

cmd/kubeadm/app/phases/controlplane/manifests.go

@@ -30,7 +30,6 @@ import (
 	"k8s.io/klog"
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
-	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	"k8s.io/kubernetes/cmd/kubeadm/app/images"
 	certphase "k8s.io/kubernetes/cmd/kubeadm/app/phases/certs"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
@@ -174,10 +173,6 @@ func getAPIServerCommand(cfg *kubeadmapi.InitConfiguration) []string {
 		}
 	}
 
-	if features.Enabled(cfg.FeatureGates, features.DynamicKubeletConfig) {
-		defaultArguments["feature-gates"] = "DynamicKubeletConfig=true"
-	}
-
 	if cfg.APIServer.ExtraArgs == nil {
 		cfg.APIServer.ExtraArgs = map[string]string{}
 	}

cmd/kubeadm/app/phases/controlplane/manifests_test.go

@@ -29,7 +29,6 @@ import (
 	"k8s.io/apimachinery/pkg/util/version"
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
-	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	"k8s.io/kubernetes/cmd/kubeadm/app/phases/certs"
 	authzmodes "k8s.io/kubernetes/pkg/kubeapiserver/authorizer/modes"
 
@@ -348,54 +347,12 @@ func TestGetAPIServerCommand(t *testing.T) {
 			},
 		},
 		{
-			name: "ensure the DynamicKubelet flag gets passed through",
-			cfg: &kubeadmapi.InitConfiguration{
-				LocalAPIEndpoint: kubeadmapi.APIEndpoint{BindPort: 123, AdvertiseAddress: "1.2.3.4"},
-				ClusterConfiguration: kubeadmapi.ClusterConfiguration{
-					Networking:      kubeadmapi.Networking{ServiceSubnet: "bar"},
-					CertificatesDir: testCertsDir,
-					FeatureGates:    map[string]bool{features.DynamicKubeletConfig: true},
-				},
-			},
-			expected: []string{
-				"kube-apiserver",
-				"--insecure-port=0",
-				"--enable-admission-plugins=NodeRestriction",
-				"--service-cluster-ip-range=bar",
-				"--service-account-key-file=" + testCertsDir + "/sa.pub",
-				"--client-ca-file=" + testCertsDir + "/ca.crt",
-				"--tls-cert-file=" + testCertsDir + "/apiserver.crt",
-				"--tls-private-key-file=" + testCertsDir + "/apiserver.key",
-				"--kubelet-client-certificate=" + testCertsDir + "/apiserver-kubelet-client.crt",
-				"--kubelet-client-key=" + testCertsDir + "/apiserver-kubelet-client.key",
-				"--enable-bootstrap-token-auth=true",
-				"--secure-port=123",
-				"--allow-privileged=true",
-				"--kubelet-preferred-address-types=InternalIP,ExternalIP,Hostname",
-				"--proxy-client-cert-file=/var/lib/certs/front-proxy-client.crt",
-				"--proxy-client-key-file=/var/lib/certs/front-proxy-client.key",
-				"--requestheader-username-headers=X-Remote-User",
-				"--requestheader-group-headers=X-Remote-Group",
-				"--requestheader-extra-headers-prefix=X-Remote-Extra-",
-				"--requestheader-client-ca-file=" + testCertsDir + "/front-proxy-ca.crt",
-				"--requestheader-allowed-names=front-proxy-client",
-				"--authorization-mode=Node,RBAC",
-				"--advertise-address=1.2.3.4",
-				fmt.Sprintf("--etcd-servers=https://127.0.0.1:%d", kubeadmconstants.EtcdListenClientPort),
-				"--etcd-cafile=" + testCertsDir + "/etcd/ca.crt",
-				"--etcd-certfile=" + testCertsDir + "/apiserver-etcd-client.crt",
-				"--etcd-keyfile=" + testCertsDir + "/apiserver-etcd-client.key",
-				"--feature-gates=DynamicKubeletConfig=true",
-			},
-		},
-		{
 			name: "test APIServer.ExtraArgs works as expected",
 			cfg: &kubeadmapi.InitConfiguration{
 				LocalAPIEndpoint: kubeadmapi.APIEndpoint{BindPort: 123, AdvertiseAddress: "1.2.3.4"},
 				ClusterConfiguration: kubeadmapi.ClusterConfiguration{
 					Networking:      kubeadmapi.Networking{ServiceSubnet: "bar"},
 					CertificatesDir: testCertsDir,
-					FeatureGates:    map[string]bool{features.DynamicKubeletConfig: true},
 					APIServer: kubeadmapi.APIServer{
 						ControlPlaneComponent: kubeadmapi.ControlPlaneComponent{
 							ExtraArgs: map[string]string{
@@ -436,7 +393,6 @@ func TestGetAPIServerCommand(t *testing.T) {
 				"--etcd-cafile=" + testCertsDir + "/etcd/ca.crt",
 				"--etcd-certfile=" + testCertsDir + "/apiserver-etcd-client.crt",
 				"--etcd-keyfile=" + testCertsDir + "/apiserver-etcd-client.key",
-				"--feature-gates=DynamicKubeletConfig=true",
 				"--audit-policy-file=/etc/config/audit.yaml",
 				"--audit-log-path=/var/log/kubernetes",
 			},

cmd/kubeadm/app/phases/kubelet/BUILD

@@ -15,7 +15,6 @@ go_library(
         "//cmd/kubeadm/app/apis/kubeadm/v1beta1:go_default_library",
         "//cmd/kubeadm/app/componentconfigs:go_default_library",
         "//cmd/kubeadm/app/constants:go_default_library",
-        "//cmd/kubeadm/app/features:go_default_library",
         "//cmd/kubeadm/app/util:go_default_library",
         "//cmd/kubeadm/app/util/apiclient:go_default_library",
         "//pkg/apis/rbac/v1:go_default_library",
@@ -45,7 +44,6 @@ go_test(
     embed = [":go_default_library"],
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
-        "//cmd/kubeadm/app/constants:go_default_library",
         "//pkg/kubelet/apis:go_default_library",
         "//pkg/kubelet/apis/config:go_default_library",
         "//staging/src/k8s.io/api/core/v1:go_default_library",

cmd/kubeadm/app/phases/kubelet/dynamic.go

@@ -31,7 +31,6 @@ import (
 
 // EnableDynamicConfigForNode updates the Node's ConfigSource to enable Dynamic Kubelet Configuration, depending on what version the kubelet is
 // Used at "kubeadm init", "kubeadm join" and "kubeadm upgrade" time
-// This func is ONLY run if the user enables the `DynamicKubeletConfig` feature gate, which is by default off
 func EnableDynamicConfigForNode(client clientset.Interface, nodeName string, kubeletVersion *version.Version) error {
 
 	configMapName := kubeadmconstants.GetKubeletConfigMapName(kubeletVersion)

cmd/kubeadm/app/phases/kubelet/flags.go

@@ -29,7 +29,6 @@ import (
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmapiv1beta1 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
-	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	nodeutil "k8s.io/kubernetes/pkg/util/node"
 	"k8s.io/kubernetes/pkg/util/procfs"
@@ -107,12 +106,6 @@ func buildKubeletArgMap(opts kubeletFlagsOpts) map[string]string {
 		kubeletFlags["hostname-override"] = opts.nodeRegOpts.Name
 	}
 
-	// If the user enabled Dynamic Kubelet Configuration (which is disabled by default), set the directory
-	// in the CLI flags so that the feature actually gets enabled
-	if features.Enabled(opts.featureGates, features.DynamicKubeletConfig) {
-		kubeletFlags["dynamic-config-dir"] = filepath.Join(constants.KubeletRunDirectory, constants.DynamicKubeletConfigurationDirectoryName)
-	}
-
 	// TODO: Conditionally set `--cgroup-driver` to either `systemd` or `cgroupfs` for CRI other than Docker
 
 	return kubeletFlags

cmd/kubeadm/app/phases/kubelet/flags_test.go

@@ -19,7 +19,6 @@ package kubelet
 import (
 	"context"
 	"errors"
-	"fmt"
 	"io"
 	"reflect"
 	"strings"
@@ -27,7 +26,6 @@ import (
 
 	"k8s.io/api/core/v1"
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
-	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
 	"k8s.io/utils/exec"
 )
 
@@ -233,26 +231,6 @@ func TestBuildKubeletArgMap(t *testing.T) {
 				"resolv-conf":                "/run/systemd/resolve/resolv.conf",
 			},
 		},
-		{
-			name: "dynamic kubelet config enabled",
-			opts: kubeletFlagsOpts{
-				nodeRegOpts: &kubeadmapi.NodeRegistrationOptions{
-					CRISocket: "/var/run/containerd.sock",
-					Name:      "foo",
-				},
-				featureGates: map[string]bool{
-					"DynamicKubeletConfig": true,
-				},
-				execer:          cgroupfsCgroupExecer,
-				pidOfFunc:       binaryNotRunningPidOfFunc,
-				defaultHostname: "foo",
-			},
-			expected: map[string]string{
-				"container-runtime":          "remote",
-				"container-runtime-endpoint": "/var/run/containerd.sock",
-				"dynamic-config-dir":         fmt.Sprintf("%s/dynamic-config", kubeadmconstants.KubeletRunDirectory),
-			},
-		},
 	}
 
 	for _, test := range tests {