Merge pull request #70024 from fabriziopandini/kubeadm-addons-config

kubeadm - addon configuration in the kubeadm config API.

cmd/kubeadm/app/apis/kubeadm/fuzzer/fuzzer.go

@@ -18,7 +18,6 @@ package fuzzer
 
 import (
 	fuzz "github.com/google/gofuzz"
-
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	runtimeserializer "k8s.io/apimachinery/pkg/runtime/serializer"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
@@ -34,6 +33,7 @@ func Funcs(codecs runtimeserializer.CodecFactory) []interface{} {
 		fuzzAuditPolicyConfiguration,
 		fuzzComponentConfigs,
 		fuzzNodeRegistration,
+		fuzzDNS,
 		fuzzLocalEtcd,
 		fuzzNetworking,
 		fuzzJoinConfiguration,
@@ -59,6 +59,9 @@ func fuzzInitConfiguration(obj *kubeadm.InitConfiguration, c fuzz.Continue) {
 			LogDir:    constants.StaticPodAuditPolicyLogDir,
 			LogMaxAge: &v1beta1.DefaultAuditPolicyLogMaxAge,
 		},
+		DNS: kubeadm.DNS{
+			Type: kubeadm.CoreDNS,
+		},
 		CertificatesDir: v1beta1.DefaultCertificatesDir,
 		ClusterName:     v1beta1.DefaultClusterName,
 		Etcd: kubeadm.Etcd{
@@ -107,6 +110,14 @@ func fuzzClusterConfiguration(obj *kubeadm.ClusterConfiguration, c fuzz.Continue
 	}
 }
 
+func fuzzDNS(obj *kubeadm.DNS, c fuzz.Continue) {
+	// This is intentionally not calling c.FuzzNoCustom because DNS struct does not exists in v1alpha3 api
+	// (so no random value will be applied, and this is necessary for getting roundtrip passing)
+
+	// Pinning values for fields that get defaults if fuzz value is empty string or nil
+	obj.Type = kubeadm.CoreDNS
+}
+
 func fuzzAuditPolicyConfiguration(obj *kubeadm.AuditPolicyConfiguration, c fuzz.Continue) {
 	c.FuzzNoCustom(obj)
 
@@ -125,6 +136,10 @@ func fuzzLocalEtcd(obj *kubeadm.LocalEtcd, c fuzz.Continue) {
 
 	// Pinning values for fields that get defaults if fuzz value is empty string or nil (thus making the round trip test fail)
 	obj.DataDir = "foo"
+
+	// Pinning values for fields that does not exists in v1alpha3 api
+	obj.ImageRepository = ""
+	obj.ImageTag = ""
 }
 
 func fuzzNetworking(obj *kubeadm.Networking, c fuzz.Continue) {

cmd/kubeadm/app/apis/kubeadm/types.go

@@ -95,10 +95,16 @@ type ClusterConfiguration struct {
 	// Scheduler contains extra settings for the scheduler control plane component
 	Scheduler ControlPlaneComponent
 
+	// DNS defines the options for the DNS add-on installed in the cluster.
+	DNS DNS
+
 	// CertificatesDir specifies where to store or look for all required certificates.
 	CertificatesDir string
 
-	// ImageRepository is the container registry to pull control plane images from.
+	// ImageRepository sets the container registry to pull images from.
+	// If empty, `k8s.gcr.io` will be used by default; in case of kubernetes version is a CI build (kubernetes version starts with `ci/` or `ci-cross/`)
+	// `gcr.io/kubernetes-ci-images` will be used as a default for control plane components and for kube-proxy, while `k8s.gcr.io`
+	// will be used for all the other images.
 	ImageRepository string
 
 	// CIImageRepository is the container registry for core images generated by CI.
@@ -122,6 +128,8 @@ type ClusterConfiguration struct {
 // ControlPlaneComponent holds settings common to control plane component of the cluster
 type ControlPlaneComponent struct {
 	// ExtraArgs is an extra set of flags to pass to the control plane component.
+	// TODO: This is temporary and ideally we would like to switch all components to
+	// use ComponentConfig + ConfigMaps.
 	ExtraArgs map[string]string
 
 	// ExtraVolumes is an extra set of host volumes, mounted to the control plane component.
@@ -139,6 +147,40 @@ type APIServer struct {
 	TimeoutForControlPlane *metav1.Duration
 }
 
+// DNSAddOnType defines string identifying DNS add-on types
+type DNSAddOnType string
+
+const (
+	// CoreDNS add-on type
+	CoreDNS DNSAddOnType = "CoreDNS"
+
+	// KubeDNS add-on type
+	KubeDNS DNSAddOnType = "kube-dns"
+)
+
+// DNS defines the DNS addon that should be used in the cluster
+type DNS struct {
+	// Type defines the DNS add-on to be used
+	Type DNSAddOnType
+
+	// ImageMeta allows to customize the image used for the DNS component
+	ImageMeta `json:",inline"`
+}
+
+// ImageMeta allows to customize the image used for components that are not
+// originated from the Kubernetes/Kubernetes release process
+type ImageMeta struct {
+	// ImageRepository sets the container registry to pull images from.
+	// if not set, the ImageRepository defined in ClusterConfiguration will be used instead.
+	ImageRepository string
+
+	// ImageTag allows to specify a tag for the image.
+	// In case this value is set, kubeadm does not change automatically the version of the above components during upgrades.
+	ImageTag string
+
+	//TODO: evaluate if we need also a ImageName based on user feedbacks
+}
+
 // ComponentConfigs holds known internal ComponentConfig types for other components
 type ComponentConfigs struct {
 	// Kubelet holds the ComponentConfiguration for the kubelet
@@ -239,11 +281,8 @@ type Etcd struct {
 
 // LocalEtcd describes that kubeadm should run an etcd cluster locally
 type LocalEtcd struct {
-
+	// ImageMeta allows to customize the container used for etcd
-	// Image specifies which container image to use for running etcd.
+	ImageMeta `json:",inline"`
-	// If empty, automatically populated by kubeadm using the image
-	// repository and default etcd version.
-	Image string
 
 	// DataDir is the directory etcd will place its data.
 	// Defaults to "/var/lib/etcd".

cmd/kubeadm/app/apis/kubeadm/v1alpha3/BUILD

@@ -20,6 +20,7 @@ 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/util:go_default_library",
         "//staging/src/k8s.io/api/core/v1:go_default_library",
@@ -56,8 +57,6 @@ go_test(
     embed = [":go_default_library"],
     deps = [
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
-        "//cmd/kubeadm/app/apis/kubeadm/scheme:go_default_library",
-        "//cmd/kubeadm/test:go_default_library",
         "//vendor/github.com/pkg/errors:go_default_library",
     ],
 )

cmd/kubeadm/app/apis/kubeadm/v1alpha3/conversion.go

@@ -17,16 +17,21 @@ limitations under the License.
 package v1alpha3
 
 import (
-	"github.com/pkg/errors"
+	"regexp"
+	"strings"
 
+	"github.com/pkg/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/conversion"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
+	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	"k8s.io/kubernetes/cmd/kubeadm/app/images"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 )
 
+var imageRegEx = regexp.MustCompile(`(?P<repository>.+/)(?P<image>[^:]+)(?P<tag>:.+)`)
+
 func Convert_v1alpha3_InitConfiguration_To_kubeadm_InitConfiguration(in *InitConfiguration, out *kubeadm.InitConfiguration, s conversion.Scope) error {
 	if err := autoConvert_v1alpha3_InitConfiguration_To_kubeadm_InitConfiguration(in, out, s); err != nil {
 		return err
@@ -133,6 +138,14 @@ func Convert_v1alpha3_ClusterConfiguration_To_kubeadm_ClusterConfiguration(in *C
 		return err
 	}
 
+	// converting v1alpha3 featureGate CoreDNS to internal DNS.Type
+	if features.Enabled(in.FeatureGates, features.CoreDNS) {
+		out.DNS.Type = kubeadm.CoreDNS
+	} else {
+		out.DNS.Type = kubeadm.KubeDNS
+	}
+	delete(out.FeatureGates, features.CoreDNS)
+
 	return nil
 }
 
@@ -174,11 +187,19 @@ func Convert_kubeadm_ClusterConfiguration_To_v1alpha3_ClusterConfiguration(in *k
 	}
 
 	if in.UseHyperKubeImage {
-		out.UnifiedControlPlaneImage = images.GetKubeControlPlaneImage("", in)
+		out.UnifiedControlPlaneImage = images.GetKubernetesImage("", in)
 	} else {
 		out.UnifiedControlPlaneImage = ""
 	}
 
+	// converting internal DNS.Type to v1alpha3 featureGate CoreDNS (this is only for getting roundtrip passing, but it is never used in reality)
+	if out.FeatureGates == nil {
+		out.FeatureGates = map[string]bool{}
+	}
+	if in.DNS.Type == kubeadm.KubeDNS {
+		out.FeatureGates[features.CoreDNS] = false
+	}
+
 	return nil
 }
 
@@ -225,5 +246,52 @@ func convertSlice_kubeadm_HostPathMount_To_v1alpha3_HostPathMount(in *[]kubeadm.
 	} else {
 		*out = nil
 	}
+
+	return nil
+}
+
+func Convert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(in *LocalEtcd, out *kubeadm.LocalEtcd, s conversion.Scope) error {
+	if err := autoConvert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(in, out, s); err != nil {
+		return err
+	}
+
+	var err error
+	out.ImageMeta, err = etcdImageToImageMeta(in.Image)
+	return err
+}
+
+func etcdImageToImageMeta(image string) (kubeadm.ImageMeta, error) {
+	// empty image -> empty image meta
+	if image == "" {
+		return kubeadm.ImageMeta{}, nil
+	}
+
+	matches := imageRegEx.FindStringSubmatch(image)
+	if len(matches) != 4 {
+		return kubeadm.ImageMeta{}, errors.New("Conversion Error: kubeadm does not support converting v1alpha3 configurations with etcd image without explicit repository or tag definition. Please fix the image name")
+	}
+
+	imageRepository := strings.TrimSuffix(matches[1], "/")
+	imageName := matches[2]
+	imageTag := strings.TrimPrefix(matches[3], ":")
+
+	if imageName != constants.Etcd {
+		return kubeadm.ImageMeta{}, errors.New("Conversion Error: kubeadm does not support converting v1alpha3 configurations with etcd imageName different than etcd. Please fix the image name")
+	}
+
+	return kubeadm.ImageMeta{
+		ImageRepository: imageRepository,
+		ImageTag:        imageTag,
+	}, nil
+}
+
+func Convert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(in *kubeadm.LocalEtcd, out *LocalEtcd, s conversion.Scope) error {
+	if err := autoConvert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(in, out, s); err != nil {
+		return err
+	}
+
+	// converting internal LocalEtcd.ImageMeta to v1alpha3 LocalEtcd.Image (this is only for getting roundtrip passing, but it is
+	// never used in reality)
+
 	return nil
 }

cmd/kubeadm/app/apis/kubeadm/v1alpha3/conversion_test.go

@@ -14,48 +14,44 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package v1alpha3_test
+package v1alpha3
 
 import (
 	"testing"
 
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
-	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/scheme"
-	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1alpha3"
-	testutil "k8s.io/kubernetes/cmd/kubeadm/test"
 )
 
 func TestJoinConfigurationConversion(t *testing.T) {
 	testcases := map[string]struct {
-		old         *v1alpha3.JoinConfiguration
+		old           *JoinConfiguration
-		expectedErr string
+		expectedError bool
 	}{
 		"conversion succeeds": {
-			old:         &v1alpha3.JoinConfiguration{},
+			old:           &JoinConfiguration{},
-			expectedErr: "",
+			expectedError: false,
 		},
 		"cluster name fails to be converted": {
-			old: &v1alpha3.JoinConfiguration{
+			old: &JoinConfiguration{
 				ClusterName: "kubernetes",
 			},
-			expectedErr: "clusterName has been removed from JoinConfiguration and clusterName from ClusterConfiguration will be used instead. Please cleanup JoinConfiguration.ClusterName fields",
+			expectedError: true,
 		},
 		"feature gates fails to be converted": {
-			old: &v1alpha3.JoinConfiguration{
+			old: &JoinConfiguration{
 				FeatureGates: map[string]bool{
 					"someGate": true,
 				},
 			},
-			expectedErr: "featureGates has been removed from JoinConfiguration and featureGates from ClusterConfiguration will be used instead. Please cleanup JoinConfiguration.FeatureGates fields",
+			expectedError: true,
 		},
 	}
 	for _, tc := range testcases {
 		internal := &kubeadm.JoinConfiguration{}
-		err := scheme.Scheme.Convert(tc.old, internal, nil)
+		err := Convert_v1alpha3_JoinConfiguration_To_kubeadm_JoinConfiguration(tc.old, internal, nil)
-		if len(tc.expectedErr) != 0 {
+		if (err != nil) != tc.expectedError {
-			testutil.AssertError(t, err, tc.expectedErr)
+			t.Errorf("ImageToImageMeta returned unexpected error: %v, saw: %v", tc.expectedError, (err != nil))
-		} else if err != nil {
+			return
-			t.Errorf("no error was expected but '%s' was found", err)
 		}
 	}
 }
@@ -63,19 +59,19 @@ func TestJoinConfigurationConversion(t *testing.T) {
 func TestConvertToUseHyperKubeImage(t *testing.T) {
 	tests := []struct {
 		desc              string
-		in                *v1alpha3.ClusterConfiguration
+		in                *ClusterConfiguration
 		useHyperKubeImage bool
 		expectedErr       bool
 	}{
 		{
 			desc:              "unset UnifiedControlPlaneImage sets UseHyperKubeImage to false",
-			in:                &v1alpha3.ClusterConfiguration{},
+			in:                &ClusterConfiguration{},
 			useHyperKubeImage: false,
 			expectedErr:       false,
 		},
 		{
 			desc: "matching UnifiedControlPlaneImage sets UseHyperKubeImage to true",
-			in: &v1alpha3.ClusterConfiguration{
+			in: &ClusterConfiguration{
 				ImageRepository:          "k8s.gcr.io",
 				KubernetesVersion:        "v1.12.2",
 				UnifiedControlPlaneImage: "k8s.gcr.io/hyperkube:v1.12.2",
@@ -85,7 +81,7 @@ func TestConvertToUseHyperKubeImage(t *testing.T) {
 		},
 		{
 			desc: "mismatching UnifiedControlPlaneImage tag causes an error",
-			in: &v1alpha3.ClusterConfiguration{
+			in: &ClusterConfiguration{
 				ImageRepository:          "k8s.gcr.io",
 				KubernetesVersion:        "v1.12.0",
 				UnifiedControlPlaneImage: "k8s.gcr.io/hyperkube:v1.12.2",
@@ -94,7 +90,7 @@ func TestConvertToUseHyperKubeImage(t *testing.T) {
 		},
 		{
 			desc: "mismatching UnifiedControlPlaneImage repo causes an error",
-			in: &v1alpha3.ClusterConfiguration{
+			in: &ClusterConfiguration{
 				ImageRepository:          "my.repo",
 				KubernetesVersion:        "v1.12.2",
 				UnifiedControlPlaneImage: "k8s.gcr.io/hyperkube:v1.12.2",
@@ -103,7 +99,7 @@ func TestConvertToUseHyperKubeImage(t *testing.T) {
 		},
 		{
 			desc: "mismatching UnifiedControlPlaneImage image name causes an error",
-			in: &v1alpha3.ClusterConfiguration{
+			in: &ClusterConfiguration{
 				ImageRepository:          "k8s.gcr.io",
 				KubernetesVersion:        "v1.12.2",
 				UnifiedControlPlaneImage: "k8s.gcr.io/otherimage:v1.12.2",
@@ -115,7 +111,7 @@ func TestConvertToUseHyperKubeImage(t *testing.T) {
 	for _, test := range tests {
 		t.Run(test.desc, func(t *testing.T) {
 			out := &kubeadm.ClusterConfiguration{}
-			err := v1alpha3.Convert_v1alpha3_UnifiedControlPlaneImage_To_kubeadm_UseHyperKubeImage(test.in, out)
+			err := Convert_v1alpha3_UnifiedControlPlaneImage_To_kubeadm_UseHyperKubeImage(test.in, out)
 			if test.expectedErr {
 				if err == nil {
 					t.Fatalf("unexpected success, UseHyperKubeImage: %t", out.UseHyperKubeImage)
@@ -131,3 +127,59 @@ func TestConvertToUseHyperKubeImage(t *testing.T) {
 		})
 	}
 }
+
+func TestEtcdImageToImageMeta(t *testing.T) {
+	tests := []struct {
+		name              string
+		image             string
+		expectedImageMeta kubeadm.ImageMeta
+		expectedError     bool
+	}{
+		{
+			name:  "Empty image -> Empty image meta",
+			image: "",
+			expectedImageMeta: kubeadm.ImageMeta{
+				ImageRepository: "",
+				ImageTag:        "",
+			},
+		},
+		{
+			name:  "image with tag and repository",
+			image: "custom.repo/etcd:custom.tag",
+			expectedImageMeta: kubeadm.ImageMeta{
+				ImageRepository: "custom.repo",
+				ImageTag:        "custom.tag",
+			},
+		},
+		{
+			name:          "image with custom imageName",
+			image:         "real.repo/custom-image-name-for-etcd:real.tag",
+			expectedError: true,
+		},
+		{
+			name:          "image without repository",
+			image:         "etcd:real.tag",
+			expectedError: true,
+		},
+		{
+			name:          "image without tag",
+			image:         "real.repo/etcd",
+			expectedError: true,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			ret, err := etcdImageToImageMeta(test.image)
+
+			if (err != nil) != test.expectedError {
+				t.Errorf("etcdImageToImageMeta returned unexpected error: %v, saw: %v", test.expectedError, (err != nil))
+				return
+			}
+
+			if ret != test.expectedImageMeta {
+				t.Errorf("etcdImageToImageMeta returned unexpected ImageMeta: %v, saw: %v", test.expectedImageMeta, ret)
+			}
+		})
+	}
+}

cmd/kubeadm/app/apis/kubeadm/v1alpha3/zz_generated.conversion.go

@@ -197,6 +197,11 @@ func RegisterConversions(s *runtime.Scheme) error {
 	}); err != nil {
 		return err
 	}
+	if err := s.AddConversionFunc((*kubeadm.LocalEtcd)(nil), (*LocalEtcd)(nil), func(a, b interface{}, scope conversion.Scope) error {
+		return Convert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(a.(*kubeadm.LocalEtcd), b.(*LocalEtcd), scope)
+	}); err != nil {
+		return err
+	}
 	if err := s.AddConversionFunc((*ClusterConfiguration)(nil), (*kubeadm.ClusterConfiguration)(nil), func(a, b interface{}, scope conversion.Scope) error {
 		return Convert_v1alpha3_ClusterConfiguration_To_kubeadm_ClusterConfiguration(a.(*ClusterConfiguration), b.(*kubeadm.ClusterConfiguration), scope)
 	}); err != nil {
@@ -217,6 +222,11 @@ func RegisterConversions(s *runtime.Scheme) error {
 	}); err != nil {
 		return err
 	}
+	if err := s.AddConversionFunc((*LocalEtcd)(nil), (*kubeadm.LocalEtcd)(nil), func(a, b interface{}, scope conversion.Scope) error {
+		return Convert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(a.(*LocalEtcd), b.(*kubeadm.LocalEtcd), scope)
+	}); err != nil {
+		return err
+	}
 	return nil
 }
 
@@ -358,6 +368,7 @@ func autoConvert_kubeadm_ClusterConfiguration_To_v1alpha3_ClusterConfiguration(i
 	// WARNING: in.APIServer requires manual conversion: does not exist in peer-type
 	// WARNING: in.ControllerManager requires manual conversion: does not exist in peer-type
 	// WARNING: in.Scheduler requires manual conversion: does not exist in peer-type
+	// WARNING: in.DNS requires manual conversion: does not exist in peer-type
 	out.CertificatesDir = in.CertificatesDir
 	out.ImageRepository = in.ImageRepository
 	// INFO: in.CIImageRepository opted out of conversion generation
@@ -391,7 +402,15 @@ func Convert_kubeadm_ClusterStatus_To_v1alpha3_ClusterStatus(in *kubeadm.Cluster
 }
 
 func autoConvert_v1alpha3_Etcd_To_kubeadm_Etcd(in *Etcd, out *kubeadm.Etcd, s conversion.Scope) error {
-	out.Local = (*kubeadm.LocalEtcd)(unsafe.Pointer(in.Local))
+	if in.Local != nil {
+		in, out := &in.Local, &out.Local
+		*out = new(kubeadm.LocalEtcd)
+		if err := Convert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(*in, *out, s); err != nil {
+			return err
+		}
+	} else {
+		out.Local = nil
+	}
 	out.External = (*kubeadm.ExternalEtcd)(unsafe.Pointer(in.External))
 	return nil
 }
@@ -402,7 +421,15 @@ func Convert_v1alpha3_Etcd_To_kubeadm_Etcd(in *Etcd, out *kubeadm.Etcd, s conver
 }
 
 func autoConvert_kubeadm_Etcd_To_v1alpha3_Etcd(in *kubeadm.Etcd, out *Etcd, s conversion.Scope) error {
-	out.Local = (*LocalEtcd)(unsafe.Pointer(in.Local))
+	if in.Local != nil {
+		in, out := &in.Local, &out.Local
+		*out = new(LocalEtcd)
+		if err := Convert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(*in, *out, s); err != nil {
+			return err
+		}
+	} else {
+		out.Local = nil
+	}
 	out.External = (*ExternalEtcd)(unsafe.Pointer(in.External))
 	return nil
 }
@@ -516,7 +543,7 @@ func autoConvert_kubeadm_JoinConfiguration_To_v1alpha3_JoinConfiguration(in *kub
 }
 
 func autoConvert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(in *LocalEtcd, out *kubeadm.LocalEtcd, s conversion.Scope) error {
-	out.Image = in.Image
+	// WARNING: in.Image requires manual conversion: does not exist in peer-type
 	out.DataDir = in.DataDir
 	out.ExtraArgs = *(*map[string]string)(unsafe.Pointer(&in.ExtraArgs))
 	out.ServerCertSANs = *(*[]string)(unsafe.Pointer(&in.ServerCertSANs))
@@ -524,13 +551,8 @@ func autoConvert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(in *LocalEtcd, out *kub
 	return nil
 }
 
-// Convert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd is an autogenerated conversion function.
-func Convert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(in *LocalEtcd, out *kubeadm.LocalEtcd, s conversion.Scope) error {
-	return autoConvert_v1alpha3_LocalEtcd_To_kubeadm_LocalEtcd(in, out, s)
-}
-
 func autoConvert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(in *kubeadm.LocalEtcd, out *LocalEtcd, s conversion.Scope) error {
-	out.Image = in.Image
+	// WARNING: in.ImageMeta requires manual conversion: does not exist in peer-type
 	out.DataDir = in.DataDir
 	out.ExtraArgs = *(*map[string]string)(unsafe.Pointer(&in.ExtraArgs))
 	out.ServerCertSANs = *(*[]string)(unsafe.Pointer(&in.ServerCertSANs))
@@ -538,11 +560,6 @@ func autoConvert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(in *kubeadm.LocalEtcd,
 	return nil
 }
 
-// Convert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd is an autogenerated conversion function.
-func Convert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(in *kubeadm.LocalEtcd, out *LocalEtcd, s conversion.Scope) error {
-	return autoConvert_kubeadm_LocalEtcd_To_v1alpha3_LocalEtcd(in, out, s)
-}
-
 func autoConvert_v1alpha3_Networking_To_kubeadm_Networking(in *Networking, out *kubeadm.Networking, s conversion.Scope) error {
 	out.ServiceSubnet = in.ServiceSubnet
 	out.PodSubnet = in.PodSubnet

cmd/kubeadm/app/apis/kubeadm/v1beta1/defaults.go

@@ -99,6 +99,7 @@ func SetDefaults_ClusterConfiguration(obj *ClusterConfiguration) {
 		obj.ClusterName = DefaultClusterName
 	}
 
+	SetDefaults_DNS(obj)
 	SetDefaults_Etcd(obj)
 	SetDefaults_AuditPolicyConfiguration(obj)
 	SetDefaults_APIServer(&obj.APIServer)
@@ -113,7 +114,14 @@ func SetDefaults_APIServer(obj *APIServer) {
 	}
 }
 
-// SetDefaults_Etcd assigns default values for the Proxy
+// SetDefaults_DNS assigns default values for the DNS component
+func SetDefaults_DNS(obj *ClusterConfiguration) {
+	if obj.DNS.Type == "" {
+		obj.DNS.Type = CoreDNS
+	}
+}
+
+// SetDefaults_Etcd assigns default values for the proxy
 func SetDefaults_Etcd(obj *ClusterConfiguration) {
 	if obj.Etcd.External == nil && obj.Etcd.Local == nil {
 		obj.Etcd.Local = &LocalEtcd{}

cmd/kubeadm/app/apis/kubeadm/v1beta1/types.go

@@ -91,10 +91,16 @@ type ClusterConfiguration struct {
 	// Scheduler contains extra settings for the scheduler control plane component
 	Scheduler ControlPlaneComponent `json:"scheduler,omitempty"`
 
+	// DNS defines the options for the DNS add-on installed in the cluster.
+	DNS DNS `json:"dns"`
+
 	// CertificatesDir specifies where to store or look for all required certificates.
 	CertificatesDir string `json:"certificatesDir"`
 
-	// ImageRepository what container registry to pull control plane images from
+	// ImageRepository sets the container registry to pull images from.
+	// If empty, `k8s.gcr.io` will be used by default; in case of kubernetes version is a CI build (kubernetes version starts with `ci/` or `ci-cross/`)
+	// `gcr.io/kubernetes-ci-images` will be used as a default for control plane components and for kube-proxy, while `k8s.gcr.io`
+	// will be used for all the other images.
 	ImageRepository string `json:"imageRepository"`
 
 	// UseHyperKubeImage controls if hyperkube should be used for Kubernetes components instead of their respective separate images
@@ -113,6 +119,8 @@ type ClusterConfiguration struct {
 // ControlPlaneComponent holds settings common to control plane component of the cluster
 type ControlPlaneComponent struct {
 	// ExtraArgs is an extra set of flags to pass to the control plane component.
+	// TODO: This is temporary and ideally we would like to switch all components to
+	// use ComponentConfig + ConfigMaps.
 	ExtraArgs map[string]string `json:"extraArgs,omitempty"`
 
 	// ExtraVolumes is an extra set of host volumes, mounted to the control plane component.
@@ -130,6 +138,40 @@ type APIServer struct {
 	TimeoutForControlPlane *metav1.Duration `json:"timeoutForControlPlane,omitempty"`
 }
 
+// DNSAddOnType defines string identifying DNS add-on types
+type DNSAddOnType string
+
+const (
+	// CoreDNS add-on type
+	CoreDNS DNSAddOnType = "CoreDNS"
+
+	// KubeDNS add-on type
+	KubeDNS DNSAddOnType = "kube-dns"
+)
+
+// DNS defines the DNS addon that should be used in the cluster
+type DNS struct {
+	// Type defines the DNS add-on to be used
+	Type DNSAddOnType `json:"type"`
+
+	// ImageMeta allows to customize the image used for the DNS component
+	ImageMeta `json:",inline"`
+}
+
+// ImageMeta allows to customize the image used for components that are not
+// originated from the Kubernetes/Kubernetes release process
+type ImageMeta struct {
+	// ImageRepository sets the container registry to pull images from.
+	// if not set, the ImageRepository defined in ClusterConfiguration will be used instead.
+	ImageRepository string `json:"imageRepository,omitempty"`
+
+	// ImageTag allows to specify a tag for the image.
+	// In case this value is set, kubeadm does not change automatically the version of the above components during upgrades.
+	ImageTag string `json:"imageTag,omitempty"`
+
+	//TODO: evaluate if we need also a ImageName based on user feedbacks
+}
+
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
 
 // ClusterStatus contains the cluster status. The ClusterStatus will be stored in the kubeadm-config
@@ -220,11 +262,8 @@ type Etcd struct {
 
 // LocalEtcd describes that kubeadm should run an etcd cluster locally
 type LocalEtcd struct {
-
+	// ImageMeta allows to customize the container used for etcd
-	// Image specifies which container image to use for running etcd.
+	ImageMeta `json:",inline"`
-	// If empty, automatically populated by kubeadm using the image
-	// repository and default etcd version.
-	Image string `json:"image"`
 
 	// DataDir is the directory etcd will place its data.
 	// Defaults to "/var/lib/etcd".

cmd/kubeadm/app/apis/kubeadm/v1beta1/zz_generated.conversion.go

@@ -127,6 +127,16 @@ func RegisterConversions(s *runtime.Scheme) error {
 	}); err != nil {
 		return err
 	}
+	if err := s.AddGeneratedConversionFunc((*DNS)(nil), (*kubeadm.DNS)(nil), func(a, b interface{}, scope conversion.Scope) error {
+		return Convert_v1beta1_DNS_To_kubeadm_DNS(a.(*DNS), b.(*kubeadm.DNS), scope)
+	}); err != nil {
+		return err
+	}
+	if err := s.AddGeneratedConversionFunc((*kubeadm.DNS)(nil), (*DNS)(nil), func(a, b interface{}, scope conversion.Scope) error {
+		return Convert_kubeadm_DNS_To_v1beta1_DNS(a.(*kubeadm.DNS), b.(*DNS), scope)
+	}); err != nil {
+		return err
+	}
 	if err := s.AddGeneratedConversionFunc((*Discovery)(nil), (*kubeadm.Discovery)(nil), func(a, b interface{}, scope conversion.Scope) error {
 		return Convert_v1beta1_Discovery_To_kubeadm_Discovery(a.(*Discovery), b.(*kubeadm.Discovery), scope)
 	}); err != nil {
@@ -177,6 +187,16 @@ func RegisterConversions(s *runtime.Scheme) error {
 	}); err != nil {
 		return err
 	}
+	if err := s.AddGeneratedConversionFunc((*ImageMeta)(nil), (*kubeadm.ImageMeta)(nil), func(a, b interface{}, scope conversion.Scope) error {
+		return Convert_v1beta1_ImageMeta_To_kubeadm_ImageMeta(a.(*ImageMeta), b.(*kubeadm.ImageMeta), scope)
+	}); err != nil {
+		return err
+	}
+	if err := s.AddGeneratedConversionFunc((*kubeadm.ImageMeta)(nil), (*ImageMeta)(nil), func(a, b interface{}, scope conversion.Scope) error {
+		return Convert_kubeadm_ImageMeta_To_v1beta1_ImageMeta(a.(*kubeadm.ImageMeta), b.(*ImageMeta), scope)
+	}); err != nil {
+		return err
+	}
 	if err := s.AddGeneratedConversionFunc((*InitConfiguration)(nil), (*kubeadm.InitConfiguration)(nil), func(a, b interface{}, scope conversion.Scope) error {
 		return Convert_v1beta1_InitConfiguration_To_kubeadm_InitConfiguration(a.(*InitConfiguration), b.(*kubeadm.InitConfiguration), scope)
 	}); err != nil {
@@ -400,6 +420,9 @@ func autoConvert_v1beta1_ClusterConfiguration_To_kubeadm_ClusterConfiguration(in
 	if err := Convert_v1beta1_ControlPlaneComponent_To_kubeadm_ControlPlaneComponent(&in.Scheduler, &out.Scheduler, s); err != nil {
 		return err
 	}
+	if err := Convert_v1beta1_DNS_To_kubeadm_DNS(&in.DNS, &out.DNS, s); err != nil {
+		return err
+	}
 	out.CertificatesDir = in.CertificatesDir
 	out.ImageRepository = in.ImageRepository
 	out.UseHyperKubeImage = in.UseHyperKubeImage
@@ -435,6 +458,9 @@ func autoConvert_kubeadm_ClusterConfiguration_To_v1beta1_ClusterConfiguration(in
 	if err := Convert_kubeadm_ControlPlaneComponent_To_v1beta1_ControlPlaneComponent(&in.Scheduler, &out.Scheduler, s); err != nil {
 		return err
 	}
+	if err := Convert_kubeadm_DNS_To_v1beta1_DNS(&in.DNS, &out.DNS, s); err != nil {
+		return err
+	}
 	out.CertificatesDir = in.CertificatesDir
 	out.ImageRepository = in.ImageRepository
 	// INFO: in.CIImageRepository opted out of conversion generation
@@ -494,6 +520,32 @@ func Convert_kubeadm_ControlPlaneComponent_To_v1beta1_ControlPlaneComponent(in *
 	return autoConvert_kubeadm_ControlPlaneComponent_To_v1beta1_ControlPlaneComponent(in, out, s)
 }
 
+func autoConvert_v1beta1_DNS_To_kubeadm_DNS(in *DNS, out *kubeadm.DNS, s conversion.Scope) error {
+	out.Type = kubeadm.DNSAddOnType(in.Type)
+	if err := Convert_v1beta1_ImageMeta_To_kubeadm_ImageMeta(&in.ImageMeta, &out.ImageMeta, s); err != nil {
+		return err
+	}
+	return nil
+}
+
+// Convert_v1beta1_DNS_To_kubeadm_DNS is an autogenerated conversion function.
+func Convert_v1beta1_DNS_To_kubeadm_DNS(in *DNS, out *kubeadm.DNS, s conversion.Scope) error {
+	return autoConvert_v1beta1_DNS_To_kubeadm_DNS(in, out, s)
+}
+
+func autoConvert_kubeadm_DNS_To_v1beta1_DNS(in *kubeadm.DNS, out *DNS, s conversion.Scope) error {
+	out.Type = DNSAddOnType(in.Type)
+	if err := Convert_kubeadm_ImageMeta_To_v1beta1_ImageMeta(&in.ImageMeta, &out.ImageMeta, s); err != nil {
+		return err
+	}
+	return nil
+}
+
+// Convert_kubeadm_DNS_To_v1beta1_DNS is an autogenerated conversion function.
+func Convert_kubeadm_DNS_To_v1beta1_DNS(in *kubeadm.DNS, out *DNS, s conversion.Scope) error {
+	return autoConvert_kubeadm_DNS_To_v1beta1_DNS(in, out, s)
+}
+
 func autoConvert_v1beta1_Discovery_To_kubeadm_Discovery(in *Discovery, out *kubeadm.Discovery, s conversion.Scope) error {
 	out.BootstrapToken = (*kubeadm.BootstrapTokenDiscovery)(unsafe.Pointer(in.BootstrapToken))
 	out.File = (*kubeadm.FileDiscovery)(unsafe.Pointer(in.File))
@@ -616,6 +668,28 @@ func Convert_kubeadm_HostPathMount_To_v1beta1_HostPathMount(in *kubeadm.HostPath
 	return autoConvert_kubeadm_HostPathMount_To_v1beta1_HostPathMount(in, out, s)
 }
 
+func autoConvert_v1beta1_ImageMeta_To_kubeadm_ImageMeta(in *ImageMeta, out *kubeadm.ImageMeta, s conversion.Scope) error {
+	out.ImageRepository = in.ImageRepository
+	out.ImageTag = in.ImageTag
+	return nil
+}
+
+// Convert_v1beta1_ImageMeta_To_kubeadm_ImageMeta is an autogenerated conversion function.
+func Convert_v1beta1_ImageMeta_To_kubeadm_ImageMeta(in *ImageMeta, out *kubeadm.ImageMeta, s conversion.Scope) error {
+	return autoConvert_v1beta1_ImageMeta_To_kubeadm_ImageMeta(in, out, s)
+}
+
+func autoConvert_kubeadm_ImageMeta_To_v1beta1_ImageMeta(in *kubeadm.ImageMeta, out *ImageMeta, s conversion.Scope) error {
+	out.ImageRepository = in.ImageRepository
+	out.ImageTag = in.ImageTag
+	return nil
+}
+
+// Convert_kubeadm_ImageMeta_To_v1beta1_ImageMeta is an autogenerated conversion function.
+func Convert_kubeadm_ImageMeta_To_v1beta1_ImageMeta(in *kubeadm.ImageMeta, out *ImageMeta, s conversion.Scope) error {
+	return autoConvert_kubeadm_ImageMeta_To_v1beta1_ImageMeta(in, out, s)
+}
+
 func autoConvert_v1beta1_InitConfiguration_To_kubeadm_InitConfiguration(in *InitConfiguration, out *kubeadm.InitConfiguration, s conversion.Scope) error {
 	if err := Convert_v1beta1_ClusterConfiguration_To_kubeadm_ClusterConfiguration(&in.ClusterConfiguration, &out.ClusterConfiguration, s); err != nil {
 		return err
@@ -695,7 +769,9 @@ func Convert_kubeadm_JoinConfiguration_To_v1beta1_JoinConfiguration(in *kubeadm.
 }
 
 func autoConvert_v1beta1_LocalEtcd_To_kubeadm_LocalEtcd(in *LocalEtcd, out *kubeadm.LocalEtcd, s conversion.Scope) error {
-	out.Image = in.Image
+	if err := Convert_v1beta1_ImageMeta_To_kubeadm_ImageMeta(&in.ImageMeta, &out.ImageMeta, s); err != nil {
+		return err
+	}
 	out.DataDir = in.DataDir
 	out.ExtraArgs = *(*map[string]string)(unsafe.Pointer(&in.ExtraArgs))
 	out.ServerCertSANs = *(*[]string)(unsafe.Pointer(&in.ServerCertSANs))
@@ -709,7 +785,9 @@ func Convert_v1beta1_LocalEtcd_To_kubeadm_LocalEtcd(in *LocalEtcd, out *kubeadm.
 }
 
 func autoConvert_kubeadm_LocalEtcd_To_v1beta1_LocalEtcd(in *kubeadm.LocalEtcd, out *LocalEtcd, s conversion.Scope) error {
-	out.Image = in.Image
+	if err := Convert_kubeadm_ImageMeta_To_v1beta1_ImageMeta(&in.ImageMeta, &out.ImageMeta, s); err != nil {
+		return err
+	}
 	out.DataDir = in.DataDir
 	out.ExtraArgs = *(*map[string]string)(unsafe.Pointer(&in.ExtraArgs))
 	out.ServerCertSANs = *(*[]string)(unsafe.Pointer(&in.ServerCertSANs))

cmd/kubeadm/app/apis/kubeadm/v1beta1/zz_generated.deepcopy.go

@@ -176,6 +176,7 @@ func (in *ClusterConfiguration) DeepCopyInto(out *ClusterConfiguration) {
 	in.APIServer.DeepCopyInto(&out.APIServer)
 	in.ControllerManager.DeepCopyInto(&out.ControllerManager)
 	in.Scheduler.DeepCopyInto(&out.Scheduler)
+	out.DNS = in.DNS
 	in.AuditPolicyConfiguration.DeepCopyInto(&out.AuditPolicyConfiguration)
 	if in.FeatureGates != nil {
 		in, out := &in.FeatureGates, &out.FeatureGates
@@ -265,6 +266,23 @@ func (in *ControlPlaneComponent) DeepCopy() *ControlPlaneComponent {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *DNS) DeepCopyInto(out *DNS) {
+	*out = *in
+	out.ImageMeta = in.ImageMeta
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new DNS.
+func (in *DNS) DeepCopy() *DNS {
+	if in == nil {
+		return nil
+	}
+	out := new(DNS)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *Discovery) DeepCopyInto(out *Discovery) {
 	*out = *in
@@ -375,6 +393,22 @@ func (in *HostPathMount) DeepCopy() *HostPathMount {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *ImageMeta) DeepCopyInto(out *ImageMeta) {
+	*out = *in
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new ImageMeta.
+func (in *ImageMeta) DeepCopy() *ImageMeta {
+	if in == nil {
+		return nil
+	}
+	out := new(ImageMeta)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *InitConfiguration) DeepCopyInto(out *InitConfiguration) {
 	*out = *in
@@ -441,6 +475,7 @@ func (in *JoinConfiguration) DeepCopyObject() runtime.Object {
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *LocalEtcd) DeepCopyInto(out *LocalEtcd) {
 	*out = *in
+	out.ImageMeta = in.ImageMeta
 	if in.ExtraArgs != nil {
 		in, out := &in.ExtraArgs, &out.ExtraArgs
 		*out = make(map[string]string, len(*in))

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

@@ -27,7 +27,6 @@ import (
 
 	"github.com/pkg/errors"
 	"github.com/spf13/pflag"
-
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/validation"
 	"k8s.io/apimachinery/pkg/util/validation/field"
@@ -407,13 +406,12 @@ func ValidateMixedArguments(flag *pflag.FlagSet) error {
 // ValidateFeatureGates validates provided feature gates
 func ValidateFeatureGates(featureGates map[string]bool, fldPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
-	validFeatures := features.Keys(features.InitFeatureGates)
 
 	// check valid feature names are provided
 	for k := range featureGates {
 		if !features.Supports(features.InitFeatureGates, k) {
 			allErrs = append(allErrs, field.Invalid(fldPath, featureGates,
-				fmt.Sprintf("%s is not a valid feature name. Valid features are: %s", k, validFeatures)))
+				fmt.Sprintf("%s is not a valid feature name.", k)))
 		}
 	}
 

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

@@ -23,7 +23,6 @@ import (
 	"time"
 
 	"github.com/spf13/pflag"
-
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/util/validation/field"
 	"k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
@@ -605,14 +604,17 @@ func TestValidateFeatureGates(t *testing.T) {
 	}{
 		{featureFlag{"Unknown": true}, false},
 		{featureFlag{"Unknown": false}, false},
-		{featureFlag{"CoreDNS": true}, true},
+		{featureFlag{"CoreDNS": true}, false},
-		{featureFlag{"CoreDNS": false}, true},
+		{featureFlag{"CoreDNS": false}, false},
+		{featureFlag{"DynamicKubeletConfig": true}, true},
+		{featureFlag{"DynamicKubeletConfig": false}, true},
 	}
 	for _, rt := range tests {
 		actual := ValidateFeatureGates(rt.featureGates, nil)
 		if (len(actual) == 0) != rt.expected {
 			t.Errorf(
-				"failed featureGates:\n\texpected: %t\n\t  actual: %t",
+				"failed featureGates %v:\n\texpected: %t\n\t  actual: %t",
+				rt.featureGates,
 				rt.expected,
 				(len(actual) == 0),
 			)

cmd/kubeadm/app/apis/kubeadm/zz_generated.deepcopy.go

@@ -179,6 +179,7 @@ func (in *ClusterConfiguration) DeepCopyInto(out *ClusterConfiguration) {
 	in.APIServer.DeepCopyInto(&out.APIServer)
 	in.ControllerManager.DeepCopyInto(&out.ControllerManager)
 	in.Scheduler.DeepCopyInto(&out.Scheduler)
+	out.DNS = in.DNS
 	in.AuditPolicyConfiguration.DeepCopyInto(&out.AuditPolicyConfiguration)
 	if in.FeatureGates != nil {
 		in, out := &in.FeatureGates, &out.FeatureGates
@@ -294,6 +295,23 @@ func (in *ControlPlaneComponent) DeepCopy() *ControlPlaneComponent {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *DNS) DeepCopyInto(out *DNS) {
+	*out = *in
+	out.ImageMeta = in.ImageMeta
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new DNS.
+func (in *DNS) DeepCopy() *DNS {
+	if in == nil {
+		return nil
+	}
+	out := new(DNS)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *Discovery) DeepCopyInto(out *Discovery) {
 	*out = *in
@@ -404,6 +422,22 @@ func (in *HostPathMount) DeepCopy() *HostPathMount {
 	return out
 }
 
+// DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
+func (in *ImageMeta) DeepCopyInto(out *ImageMeta) {
+	*out = *in
+	return
+}
+
+// DeepCopy is an autogenerated deepcopy function, copying the receiver, creating a new ImageMeta.
+func (in *ImageMeta) DeepCopy() *ImageMeta {
+	if in == nil {
+		return nil
+	}
+	out := new(ImageMeta)
+	in.DeepCopyInto(out)
+	return out
+}
+
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *InitConfiguration) DeepCopyInto(out *InitConfiguration) {
 	*out = *in
@@ -470,6 +504,7 @@ func (in *JoinConfiguration) DeepCopyObject() runtime.Object {
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *LocalEtcd) DeepCopyInto(out *LocalEtcd) {
 	*out = *in
+	out.ImageMeta = in.ImageMeta
 	if in.ExtraArgs != nil {
 		in, out := &in.ExtraArgs, &out.ExtraArgs
 		*out = make(map[string]string, len(*in))

cmd/kubeadm/app/cmd/BUILD

@@ -95,7 +95,6 @@ go_test(
         "//cmd/kubeadm/app/apis/kubeadm/validation: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/preflight:go_default_library",
         "//cmd/kubeadm/app/util:go_default_library",
         "//cmd/kubeadm/app/util/config:go_default_library",

cmd/kubeadm/app/cmd/config_test.go

@@ -29,11 +29,9 @@ import (
 
 	"github.com/renstrom/dedent"
 	"github.com/spf13/cobra"
-
 	kubeadmapiv1beta1 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1"
 	"k8s.io/kubernetes/cmd/kubeadm/app/componentconfigs"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
-	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	configutil "k8s.io/kubernetes/cmd/kubeadm/app/util/config"
 	utilruntime "k8s.io/kubernetes/cmd/kubeadm/app/util/runtime"
@@ -89,8 +87,6 @@ func TestImagesListRunWithCustomConfigPath(t *testing.T) {
 				apiVersion: kubeadm.k8s.io/v1beta1
 				kind: ClusterConfiguration
 				kubernetesVersion: v1.11.0
-				featureGates:
-				  CoreDNS: true
 			`)),
 		},
 	}
@@ -167,14 +163,23 @@ func TestConfigImagesListRunWithoutPath(t *testing.T) {
 			name: "coredns enabled",
 			cfg: kubeadmapiv1beta1.InitConfiguration{
 				ClusterConfiguration: kubeadmapiv1beta1.ClusterConfiguration{
-					FeatureGates: map[string]bool{
-						features.CoreDNS: true,
-					},
 					KubernetesVersion: dummyKubernetesVersion,
 				},
 			},
 			expectedImages: defaultNumberOfImages,
 		},
+		{
+			name: "kube-dns enabled",
+			cfg: kubeadmapiv1beta1.InitConfiguration{
+				ClusterConfiguration: kubeadmapiv1beta1.ClusterConfiguration{
+					KubernetesVersion: dummyKubernetesVersion,
+					DNS: kubeadmapiv1beta1.DNS{
+						Type: kubeadmapiv1beta1.KubeDNS,
+					},
+				},
+			},
+			expectedImages: defaultNumberOfImages + 2,
+		},
 	}
 
 	for _, tc := range testcases {

cmd/kubeadm/app/cmd/upgrade/common_test.go

@@ -41,6 +41,9 @@ func TestPrintConfiguration(t *testing.T) {
 						DataDir: "/some/path",
 					},
 				},
+				DNS: kubeadmapi.DNS{
+					Type: kubeadmapi.CoreDNS,
+				},
 			},
 			expectedBytes: []byte(`[upgrade/config] Configuration used:
 	apiServer: {}
@@ -51,10 +54,11 @@ func TestPrintConfiguration(t *testing.T) {
 	certificatesDir: ""
 	controlPlaneEndpoint: ""
 	controllerManager: {}
+	dns:
+	  type: CoreDNS
 	etcd:
 	  local:
 	    dataDir: /some/path
-	    image: ""
 	imageRepository: ""
 	kind: ClusterConfiguration
 	kubernetesVersion: v1.7.1
@@ -76,6 +80,9 @@ func TestPrintConfiguration(t *testing.T) {
 						Endpoints: []string{"https://one-etcd-instance:2379"},
 					},
 				},
+				DNS: kubeadmapi.DNS{
+					Type: kubeadmapi.CoreDNS,
+				},
 			},
 			expectedBytes: []byte(`[upgrade/config] Configuration used:
 	apiServer: {}
@@ -86,6 +93,8 @@ func TestPrintConfiguration(t *testing.T) {
 	certificatesDir: ""
 	controlPlaneEndpoint: ""
 	controllerManager: {}
+	dns:
+	  type: CoreDNS
 	etcd:
 	  external:
 	    caFile: ""

cmd/kubeadm/app/cmd/upgrade/plan.go

@@ -28,9 +28,9 @@ import (
 	"github.com/spf13/cobra"
 	"k8s.io/apimachinery/pkg/util/version"
 	"k8s.io/klog"
+	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/apis/kubeadm/validation"
-	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
 	"k8s.io/kubernetes/cmd/kubeadm/app/phases/upgrade"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	configutil "k8s.io/kubernetes/cmd/kubeadm/app/util/config"
@@ -121,7 +121,7 @@ func RunPlan(flags *planFlags) error {
 
 	// Compute which upgrade possibilities there are
 	klog.V(1).Infof("[upgrade/plan] computing upgrade possibilities")
-	availUpgrades, err := upgrade.GetAvailableUpgrades(upgradeVars.versionGetter, flags.allowExperimentalUpgrades, flags.allowRCUpgrades, etcdClient, upgradeVars.cfg.FeatureGates, upgradeVars.client)
+	availUpgrades, err := upgrade.GetAvailableUpgrades(upgradeVars.versionGetter, flags.allowExperimentalUpgrades, flags.allowRCUpgrades, etcdClient, upgradeVars.cfg.DNS.Type, upgradeVars.client)
 	if err != nil {
 		return errors.Wrap(err, "[upgrade/versions] FATAL")
 	}
@@ -207,19 +207,19 @@ func printAvailableUpgrades(upgrades []upgrade.Upgrade, w io.Writer, isExternalE
 		coreDNSBeforeVersion, coreDNSAfterVersion, kubeDNSBeforeVersion, kubeDNSAfterVersion := "", "", "", ""
 
 		switch upgrade.Before.DNSType {
-		case constants.CoreDNS:
+		case kubeadmapi.CoreDNS:
 			printCoreDNS = true
 			coreDNSBeforeVersion = upgrade.Before.DNSVersion
-		case constants.KubeDNS:
+		case kubeadmapi.KubeDNS:
 			printKubeDNS = true
 			kubeDNSBeforeVersion = upgrade.Before.DNSVersion
 		}
 
 		switch upgrade.After.DNSType {
-		case constants.CoreDNS:
+		case kubeadmapi.CoreDNS:
 			printCoreDNS = true
 			coreDNSAfterVersion = upgrade.After.DNSVersion
-		case constants.KubeDNS:
+		case kubeadmapi.KubeDNS:
 			printKubeDNS = true
 			kubeDNSAfterVersion = upgrade.After.DNSVersion
 		}

cmd/kubeadm/app/cmd/upgrade/plan_test.go

@@ -21,6 +21,7 @@ import (
 	"reflect"
 	"testing"
 
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/cmd/kubeadm/app/phases/upgrade"
 )
 
@@ -91,14 +92,14 @@ func TestPrintAvailableUpgrades(t *testing.T) {
 							"v1.8.1": 1,
 						},
 						KubeadmVersion: "v1.8.2",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.8.3",
 						KubeadmVersion: "v1.8.3",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
@@ -139,14 +140,14 @@ _____________________________________________________________________
 							"v1.8.3": 1,
 						},
 						KubeadmVersion: "v1.9.0",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.9.0",
 						KubeadmVersion: "v1.9.0",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.13",
 						EtcdVersion:    "3.1.12",
 					},
@@ -185,14 +186,14 @@ _____________________________________________________________________
 							"v1.8.3": 1,
 						},
 						KubeadmVersion: "v1.8.3",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.8.5",
 						KubeadmVersion: "v1.8.3",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
@@ -205,14 +206,14 @@ _____________________________________________________________________
 							"v1.8.3": 1,
 						},
 						KubeadmVersion: "v1.8.3",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.9.0",
 						KubeadmVersion: "v1.9.0",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.13",
 						EtcdVersion:    "3.1.12",
 					},
@@ -273,14 +274,14 @@ _____________________________________________________________________
 							"v1.8.5": 1,
 						},
 						KubeadmVersion: "v1.8.5",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.9.0-beta.1",
 						KubeadmVersion: "v1.9.0-beta.1",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.13",
 						EtcdVersion:    "3.1.12",
 					},
@@ -321,14 +322,14 @@ _____________________________________________________________________
 							"v1.8.5": 1,
 						},
 						KubeadmVersion: "v1.8.5",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.9.0-rc.1",
 						KubeadmVersion: "v1.9.0-rc.1",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.13",
 						EtcdVersion:    "3.1.12",
 					},
@@ -370,14 +371,14 @@ _____________________________________________________________________
 							"v1.9.3": 2,
 						},
 						KubeadmVersion: "v1.9.2",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.9.3",
 						KubeadmVersion: "v1.9.3",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.8",
 						EtcdVersion:    "3.1.12",
 					},
@@ -420,14 +421,14 @@ _____________________________________________________________________
 							"v1.9.2": 1,
 						},
 						KubeadmVersion: "v1.9.2",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.5",
 						EtcdVersion:    "3.0.17",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.9.3",
 						KubeadmVersion: "v1.9.3",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.8",
 						EtcdVersion:    "3.1.12",
 					},
@@ -472,14 +473,14 @@ _____________________________________________________________________
 							"v1.10.2": 1,
 						},
 						KubeadmVersion: "v1.11.0",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.7",
 						EtcdVersion:    "3.1.11",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.11.0",
 						KubeadmVersion: "v1.11.0",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -519,14 +520,14 @@ _____________________________________________________________________
 							"v1.10.2": 1,
 						},
 						KubeadmVersion: "v1.11.0",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.5",
 						EtcdVersion:    "3.1.11",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.11.0",
 						KubeadmVersion: "v1.11.0",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -565,14 +566,14 @@ _____________________________________________________________________
 							"v1.10.2": 1,
 						},
 						KubeadmVersion: "v1.11.0",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.11",
 					},
 					After: upgrade.ClusterState{
 						KubeVersion:    "v1.11.0",
 						KubeadmVersion: "v1.11.0",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.9",
 						EtcdVersion:    "3.2.18",
 					},

cmd/kubeadm/app/constants/BUILD

@@ -11,6 +11,7 @@ go_library(
     srcs = ["constants.go"],
     importpath = "k8s.io/kubernetes/cmd/kubeadm/app/constants",
     deps = [
+        "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//pkg/registry/core/service/ipallocator:go_default_library",
         "//staging/src/k8s.io/api/core/v1:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/version:go_default_library",
@@ -37,6 +38,7 @@ go_test(
     srcs = ["constants_test.go"],
     embed = [":go_default_library"],
     deps = [
+        "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/util/version:go_default_library",
         "//vendor/github.com/pkg/errors:go_default_library",
     ],

cmd/kubeadm/app/constants/constants.go

@@ -30,6 +30,7 @@ import (
 	"k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/util/version"
 	bootstrapapi "k8s.io/cluster-bootstrap/token/api"
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/pkg/registry/core/service/ipallocator"
 )
 
@@ -283,10 +284,29 @@ const (
 	// DefaultCIImageRepository points to image registry where CI uploads images from ci-cross build job
 	DefaultCIImageRepository = "gcr.io/kubernetes-ci-images"
 
-	// CoreDNS defines a variable used internally when referring to the CoreDNS addon for a cluster
+	// CoreDNSConfigMap specifies in what ConfigMap in the kube-system namespace the CoreDNS config should be stored
-	CoreDNS = "coredns"
+	CoreDNSConfigMap = "coredns"
-	// KubeDNS defines a variable used internally when referring to the kube-dns addon for a cluster
+
-	KubeDNS = "kube-dns"
+	// CoreDNSDeploymentName specifies the name of the Deployment for CoreDNS add-on
+	CoreDNSDeploymentName = "coredns"
+
+	// CoreDNSImageName specifies the name of the image for CoreDNS add-on
+	CoreDNSImageName = "coredns"
+
+	// KubeDNSConfigMap specifies in what ConfigMap in the kube-system namespace the kube-dns config should be stored
+	KubeDNSConfigMap = "kube-dns"
+
+	// KubeDNSDeploymentName specifies the name of the Deployment for kube-dns add-on
+	KubeDNSDeploymentName = "kube-dns"
+
+	// KubeDNSKubeDNSImageName specifies the name of the image for the kubedns container in the kube-dns add-on
+	KubeDNSKubeDNSImageName = "k8s-dns-kube-dns"
+
+	// KubeDNSSidecarImageName specifies the name of the image for the sidecar container in the kube-dns add-on
+	KubeDNSSidecarImageName = "k8s-dns-sidecar"
+
+	// KubeDNSDnsMasqNannyImageName specifies the name of the image for the dnsmasq container in the kube-dns add-on
+	KubeDNSDnsMasqNannyImageName = "k8s-dns-dnsmasq-nanny"
 
 	// CRICtlPackage defines the go package that installs crictl
 	CRICtlPackage = "github.com/kubernetes-incubator/cri-tools/cmd/crictl"
@@ -474,12 +494,12 @@ func GetStaticPodAuditPolicyFile() string {
 }
 
 // GetDNSVersion is a handy function that returns the DNS version by DNS type
-func GetDNSVersion(dnsType string) string {
+func GetDNSVersion(dnsType kubeadmapi.DNSAddOnType) string {
 	switch dnsType {
-	case CoreDNS:
+	case kubeadmapi.KubeDNS:
-		return CoreDNSVersion
-	default:
 		return KubeDNSVersion
+	default:
+		return CoreDNSVersion
 	}
 }
 

cmd/kubeadm/app/constants/constants_test.go

@@ -24,6 +24,7 @@ import (
 	"github.com/pkg/errors"
 
 	"k8s.io/apimachinery/pkg/util/version"
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 )
 
 func TestGetStaticPodDirectory(t *testing.T) {
@@ -203,15 +204,15 @@ func TestEtcdSupportedVersion(t *testing.T) {
 
 func TestGetKubeDNSVersion(t *testing.T) {
 	var tests = []struct {
-		dns      string
+		dns      kubeadmapi.DNSAddOnType
 		expected string
 	}{
 		{
-			dns:      KubeDNS,
+			dns:      kubeadmapi.KubeDNS,
 			expected: KubeDNSVersion,
 		},
 		{
-			dns:      CoreDNS,
+			dns:      kubeadmapi.CoreDNS,
 			expected: CoreDNSVersion,
 		},
 	}

cmd/kubeadm/app/features/features.go

@@ -23,7 +23,6 @@ import (
 	"strings"
 
 	"github.com/pkg/errors"
-
 	"k8s.io/apimachinery/pkg/util/version"
 	utilfeature "k8s.io/apiserver/pkg/util/feature"
 )
@@ -40,9 +39,12 @@ const (
 	Auditing = "Auditing"
 )
 
+var coreDNSMessage = "featureGates:CoreDNS has been removed in v1.13\n" +
+	"\tUse kubeadm-config to select which DNS addon to install."
+
 // InitFeatureGates are the default feature gates for the init command
 var InitFeatureGates = FeatureList{
-	CoreDNS:              {FeatureSpec: utilfeature.FeatureSpec{Default: true, PreRelease: utilfeature.GA}},
+	CoreDNS:              {FeatureSpec: utilfeature.FeatureSpec{Default: true, PreRelease: utilfeature.Deprecated}, HiddenInHelpText: true, DeprecationMessage: coreDNSMessage},
 	DynamicKubeletConfig: {FeatureSpec: utilfeature.FeatureSpec{Default: false, PreRelease: utilfeature.Beta}},
 	Auditing:             {FeatureSpec: utilfeature.FeatureSpec{Default: false, PreRelease: utilfeature.Alpha}},
 }
@@ -90,9 +92,9 @@ func Enabled(featureList map[string]bool, featureName string) bool {
 // Supports indicates whether a feature name is supported on the given
 // feature set
 func Supports(featureList FeatureList, featureName string) bool {
-	for k := range featureList {
+	for k, v := range featureList {
 		if featureName == string(k) {
-			return true
+			return v.PreRelease != utilfeature.Deprecated
 		}
 	}
 	return false

cmd/kubeadm/app/images/BUILD

@@ -13,7 +13,6 @@ 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/util:go_default_library",
     ],
 )

cmd/kubeadm/app/images/images.go

@@ -21,7 +21,6 @@ import (
 
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
-	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 )
 
@@ -30,8 +29,9 @@ func GetGenericImage(prefix, image, tag string) string {
 	return fmt.Sprintf("%s/%s:%s", prefix, image, tag)
 }
 
-// GetKubeControlPlaneImage generates and returns the image for the core Kubernetes components or returns the unified control plane image if specified
+// GetKubernetesImage generates and returns the image for the components managed in the Kubernetes main repository,
-func GetKubeControlPlaneImage(image string, cfg *kubeadmapi.ClusterConfiguration) string {
+// including the control-plane components ad kube-proxy. If specified, the HyperKube image will be used.
+func GetKubernetesImage(image string, cfg *kubeadmapi.ClusterConfiguration) string {
 	if cfg.UseHyperKubeImage {
 		image = constants.HyperKube
 	}
@@ -40,17 +40,44 @@ func GetKubeControlPlaneImage(image string, cfg *kubeadmapi.ClusterConfiguration
 	return GetGenericImage(repoPrefix, image, kubernetesImageTag)
 }
 
-// GetEtcdImage generates and returns the image for etcd or returns cfg.Etcd.Local.Image if specified
+// GetDNSImage generates and returns the image for the DNS, that can be CoreDNS or kube-dns.
+// Given that kube-dns uses 3 containers, an additional imageName parameter was added
+func GetDNSImage(cfg *kubeadmapi.ClusterConfiguration, imageName string) string {
+	// DNS uses default image repository by default
+	dnsImageRepository := cfg.ImageRepository
+	// unless an override is specified
+	if cfg.DNS.ImageRepository != "" {
+		dnsImageRepository = cfg.DNS.ImageRepository
+	}
+	// DNS uses an imageTag that corresponds to the DNS version matching the Kubernetes version
+	dnsImageTag := constants.GetDNSVersion(cfg.DNS.Type)
+
+	// unless an override is specified
+	if cfg.DNS.ImageTag != "" {
+		dnsImageTag = cfg.DNS.ImageTag
+	}
+	return GetGenericImage(dnsImageRepository, imageName, dnsImageTag)
+}
+
+// GetEtcdImage generates and returns the image for etcd
 func GetEtcdImage(cfg *kubeadmapi.ClusterConfiguration) string {
-	if cfg.Etcd.Local != nil && cfg.Etcd.Local.Image != "" {
+	// Etcd uses default image repository by default
-		return cfg.Etcd.Local.Image
+	etcdImageRepository := cfg.ImageRepository
+	// unless an override is specified
+	if cfg.Etcd.Local != nil && cfg.Etcd.Local.ImageRepository != "" {
+		etcdImageRepository = cfg.Etcd.Local.ImageRepository
 	}
+	// Etcd uses an imageTag that corresponds to the etcd version matching the Kubernetes version
 	etcdImageTag := constants.DefaultEtcdVersion
-	etcdImageVersion, err := constants.EtcdSupportedVersion(cfg.KubernetesVersion)
+	etcdVersion, err := constants.EtcdSupportedVersion(cfg.KubernetesVersion)
 	if err == nil {
-		etcdImageTag = etcdImageVersion.String()
+		etcdImageTag = etcdVersion.String()
 	}
-	return GetGenericImage(cfg.ImageRepository, constants.Etcd, etcdImageTag)
+	// unless an override is specified
+	if cfg.Etcd.Local != nil && cfg.Etcd.Local.ImageTag != "" {
+		etcdImageTag = cfg.Etcd.Local.ImageTag
+	}
+	return GetGenericImage(etcdImageRepository, constants.Etcd, etcdImageTag)
 }
 
 // GetAllImages returns a list of container images kubeadm expects to use on a control plane node
@@ -59,15 +86,15 @@ func GetAllImages(cfg *kubeadmapi.ClusterConfiguration) []string {
 
 	// start with core kubernetes images
 	if cfg.UseHyperKubeImage {
-		imgs = append(imgs, GetKubeControlPlaneImage(constants.HyperKube, cfg))
+		imgs = append(imgs, GetKubernetesImage(constants.HyperKube, cfg))
 	} else {
-		imgs = append(imgs, GetKubeControlPlaneImage(constants.KubeAPIServer, cfg))
+		imgs = append(imgs, GetKubernetesImage(constants.KubeAPIServer, cfg))
-		imgs = append(imgs, GetKubeControlPlaneImage(constants.KubeControllerManager, cfg))
+		imgs = append(imgs, GetKubernetesImage(constants.KubeControllerManager, cfg))
-		imgs = append(imgs, GetKubeControlPlaneImage(constants.KubeScheduler, cfg))
+		imgs = append(imgs, GetKubernetesImage(constants.KubeScheduler, cfg))
-		imgs = append(imgs, GetKubeControlPlaneImage(constants.KubeProxy, cfg))
+		imgs = append(imgs, GetKubernetesImage(constants.KubeProxy, cfg))
 	}
 
-	// pause, etcd and kube-dns are not available on the ci image repository so use the default image repository.
+	// pause is not available on the ci image repository so use the default image repository.
 	imgs = append(imgs, GetGenericImage(cfg.ImageRepository, "pause", constants.PauseVersion))
 
 	// if etcd is not external then add the image as it will be required
@@ -76,12 +103,12 @@ func GetAllImages(cfg *kubeadmapi.ClusterConfiguration) []string {
 	}
 
 	// Append the appropriate DNS images
-	if features.Enabled(cfg.FeatureGates, features.CoreDNS) {
+	if cfg.DNS.Type == kubeadmapi.CoreDNS {
-		imgs = append(imgs, GetGenericImage(cfg.ImageRepository, constants.CoreDNS, constants.CoreDNSVersion))
+		imgs = append(imgs, GetDNSImage(cfg, constants.CoreDNSImageName))
 	} else {
-		imgs = append(imgs, GetGenericImage(cfg.ImageRepository, "k8s-dns-kube-dns", constants.KubeDNSVersion))
+		imgs = append(imgs, GetDNSImage(cfg, constants.KubeDNSKubeDNSImageName))
-		imgs = append(imgs, GetGenericImage(cfg.ImageRepository, "k8s-dns-sidecar", constants.KubeDNSVersion))
+		imgs = append(imgs, GetDNSImage(cfg, constants.KubeDNSSidecarImageName))
-		imgs = append(imgs, GetGenericImage(cfg.ImageRepository, "k8s-dns-dnsmasq-nanny", constants.KubeDNSVersion))
+		imgs = append(imgs, GetDNSImage(cfg, constants.KubeDNSDnsMasqNannyImageName))
 	}
 
 	return imgs

cmd/kubeadm/app/images/images_test.go

@@ -44,7 +44,7 @@ func TestGetGenericImage(t *testing.T) {
 	}
 }
 
-func TestGetKubeControlPlaneImage(t *testing.T) {
+func TestGetKubernetesImage(t *testing.T) {
 	var tests = []struct {
 		image    string
 		expected string
@@ -84,10 +84,10 @@ func TestGetKubeControlPlaneImage(t *testing.T) {
 		},
 	}
 	for _, rt := range tests {
-		actual := GetKubeControlPlaneImage(rt.image, rt.cfg)
+		actual := GetKubernetesImage(rt.image, rt.cfg)
 		if actual != rt.expected {
 			t.Errorf(
-				"failed GetKubeControlPlaneImage:\n\texpected: %s\n\t  actual: %s",
+				"failed GetKubernetesImage:\n\texpected: %s\n\t  actual: %s",
 				rt.expected,
 				actual,
 			)
@@ -101,15 +101,43 @@ func TestGetEtcdImage(t *testing.T) {
 		cfg      *kubeadmapi.ClusterConfiguration
 	}{
 		{
-			expected: "override",
 			cfg: &kubeadmapi.ClusterConfiguration{
+				ImageRepository:   "real.repo",
+				KubernetesVersion: "1.12.0",
+				Etcd: kubeadmapi.Etcd{
+					Local: &kubeadmapi.LocalEtcd{},
+				},
+			},
+			expected: "real.repo/etcd:3.2.24",
+		},
+		{
+			cfg: &kubeadmapi.ClusterConfiguration{
+				ImageRepository:   "real.repo",
+				KubernetesVersion: "1.12.0",
 				Etcd: kubeadmapi.Etcd{
 					Local: &kubeadmapi.LocalEtcd{
-						Image: "override",
+						ImageMeta: kubeadmapi.ImageMeta{
+							ImageTag: "override",
 						},
 					},
 				},
 			},
+			expected: "real.repo/etcd:override",
+		},
+		{
+			cfg: &kubeadmapi.ClusterConfiguration{
+				ImageRepository:   "real.repo",
+				KubernetesVersion: "1.12.0",
+				Etcd: kubeadmapi.Etcd{
+					Local: &kubeadmapi.LocalEtcd{
+						ImageMeta: kubeadmapi.ImageMeta{
+							ImageRepository: "override",
+						},
+					},
+				},
+			},
+			expected: "override/etcd:3.2.24",
+		},
 		{
 			expected: GetGenericImage(gcrPrefix, "etcd", constants.DefaultEtcdVersion),
 			cfg: &kubeadmapi.ClusterConfiguration{
@@ -162,38 +190,38 @@ func TestGetAllImages(t *testing.T) {
 		{
 			name: "CoreDNS image is returned",
 			cfg: &kubeadmapi.ClusterConfiguration{
-				FeatureGates: map[string]bool{
+				DNS: kubeadmapi.DNS{
-					"CoreDNS": true,
+					Type: kubeadmapi.CoreDNS,
 				},
 			},
-			expect: constants.CoreDNS,
+			expect: constants.CoreDNSImageName,
 		},
 		{
 			name: "main kube-dns image is returned",
 			cfg: &kubeadmapi.ClusterConfiguration{
-				FeatureGates: map[string]bool{
+				DNS: kubeadmapi.DNS{
-					"CoreDNS": false,
+					Type: kubeadmapi.KubeDNS,
 				},
 			},
-			expect: "k8s-dns-kube-dns",
+			expect: constants.KubeDNSKubeDNSImageName,
 		},
 		{
 			name: "kube-dns sidecar image is returned",
 			cfg: &kubeadmapi.ClusterConfiguration{
-				FeatureGates: map[string]bool{
+				DNS: kubeadmapi.DNS{
-					"CoreDNS": false,
+					Type: kubeadmapi.KubeDNS,
 				},
 			},
-			expect: "k8s-dns-sidecar",
+			expect: constants.KubeDNSSidecarImageName,
 		},
 		{
 			name: "kube-dns dnsmasq-nanny image is returned",
 			cfg: &kubeadmapi.ClusterConfiguration{
-				FeatureGates: map[string]bool{
+				DNS: kubeadmapi.DNS{
-					"CoreDNS": false,
+					Type: kubeadmapi.KubeDNS,
 				},
 			},
-			expect: "k8s-dns-dnsmasq-nanny",
+			expect: constants.KubeDNSDnsMasqNannyImageName,
 		},
 	}
 	for _, tc := range testcases {

cmd/kubeadm/app/phases/addons/dns/BUILD

@@ -33,7 +33,7 @@ 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/util:go_default_library",
         "//cmd/kubeadm/app/util/apiclient:go_default_library",
         "//staging/src/k8s.io/api/apps/v1:go_default_library",

cmd/kubeadm/app/phases/addons/dns/dns.go

@@ -23,7 +23,6 @@ import (
 
 	"github.com/mholt/caddy/caddyfile"
 	"github.com/pkg/errors"
-
 	apps "k8s.io/api/apps/v1"
 	"k8s.io/api/core/v1"
 	rbac "k8s.io/api/rbac/v1"
@@ -34,7 +33,7 @@ import (
 	clientsetscheme "k8s.io/client-go/kubernetes/scheme"
 	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"
 	kubeadmutil "k8s.io/kubernetes/cmd/kubeadm/app/util"
 	"k8s.io/kubernetes/cmd/kubeadm/app/util/apiclient"
 )
@@ -48,7 +47,7 @@ const (
 )
 
 // DeployedDNSAddon returns the type of DNS addon currently deployed
-func DeployedDNSAddon(client clientset.Interface) (string, string, error) {
+func DeployedDNSAddon(client clientset.Interface) (kubeadmapi.DNSAddOnType, string, error) {
 	deploymentsClient := client.AppsV1().Deployments(metav1.NamespaceSystem)
 	deployments, err := deploymentsClient.List(metav1.ListOptions{LabelSelector: "k8s-app=kube-dns"})
 	if err != nil {
@@ -60,10 +59,14 @@ func DeployedDNSAddon(client clientset.Interface) (string, string, error) {
 		return "", "", nil
 	case 1:
 		addonName := deployments.Items[0].Name
+		addonType := kubeadmapi.CoreDNS
+		if addonName == kubeadmconstants.KubeDNSDeploymentName {
+			addonType = kubeadmapi.KubeDNS
+		}
 		addonImage := deployments.Items[0].Spec.Template.Spec.Containers[0].Image
 		addonImageParts := strings.Split(addonImage, ":")
 		addonVersion := addonImageParts[len(addonImageParts)-1]
-		return addonName, addonVersion, nil
+		return addonType, addonVersion, nil
 	default:
 		return "", "", errors.Errorf("multiple DNS addon deployments found: %v", deployments.Items)
 	}
@@ -71,7 +74,7 @@ func DeployedDNSAddon(client clientset.Interface) (string, string, error) {
 
 // EnsureDNSAddon creates the kube-dns or CoreDNS addon
 func EnsureDNSAddon(cfg *kubeadmapi.InitConfiguration, client clientset.Interface) error {
-	if features.Enabled(cfg.FeatureGates, features.CoreDNS) {
+	if cfg.DNS.Type == kubeadmapi.CoreDNS {
 		return coreDNSAddon(cfg, client)
 	}
 	return kubeDNSAddon(cfg, client)
@@ -97,9 +100,11 @@ func kubeDNSAddon(cfg *kubeadmapi.InitConfiguration, client clientset.Interface)
 	}
 
 	dnsDeploymentBytes, err := kubeadmutil.ParseTemplate(KubeDNSDeployment,
-		struct{ ImageRepository, Version, DNSBindAddr, DNSProbeAddr, DNSDomain, MasterTaintKey string }{
+		struct{ DeploymentName, KubeDNSImage, DNSMasqImage, SidecarImage, DNSBindAddr, DNSProbeAddr, DNSDomain, MasterTaintKey string }{
-			ImageRepository: cfg.ImageRepository,
+			DeploymentName: kubeadmconstants.KubeDNSDeploymentName,
-			Version:         kubeadmconstants.KubeDNSVersion,
+			KubeDNSImage:   images.GetDNSImage(&cfg.ClusterConfiguration, kubeadmconstants.KubeDNSKubeDNSImageName),
+			DNSMasqImage:   images.GetDNSImage(&cfg.ClusterConfiguration, kubeadmconstants.KubeDNSDnsMasqNannyImageName),
+			SidecarImage:   images.GetDNSImage(&cfg.ClusterConfiguration, kubeadmconstants.KubeDNSSidecarImageName),
 			DNSBindAddr:    dnsBindAddr,
 			DNSProbeAddr:   dnsProbeAddr,
 			DNSDomain:      cfg.Networking.DNSDomain,
@@ -151,17 +156,17 @@ func createKubeDNSAddon(deploymentBytes, serviceBytes []byte, client clientset.I
 
 func coreDNSAddon(cfg *kubeadmapi.InitConfiguration, client clientset.Interface) error {
 	// Get the YAML manifest
-	coreDNSDeploymentBytes, err := kubeadmutil.ParseTemplate(CoreDNSDeployment, struct{ ImageRepository, MasterTaintKey, Version string }{
+	coreDNSDeploymentBytes, err := kubeadmutil.ParseTemplate(CoreDNSDeployment, struct{ DeploymentName, Image, MasterTaintKey string }{
-		ImageRepository: cfg.ImageRepository,
+		DeploymentName: kubeadmconstants.CoreDNSDeploymentName,
+		Image:          images.GetDNSImage(&cfg.ClusterConfiguration, kubeadmconstants.CoreDNSImageName),
 		MasterTaintKey: kubeadmconstants.LabelNodeRoleMaster,
-		Version:         kubeadmconstants.CoreDNSVersion,
 	})
 	if err != nil {
 		return errors.Wrap(err, "error when parsing CoreDNS deployment template")
 	}
 
 	// Get the kube-dns ConfigMap for translation to equivalent CoreDNS Config.
-	kubeDNSConfigMap, err := client.CoreV1().ConfigMaps(metav1.NamespaceSystem).Get(kubeadmconstants.KubeDNS, metav1.GetOptions{})
+	kubeDNSConfigMap, err := client.CoreV1().ConfigMaps(metav1.NamespaceSystem).Get(kubeadmconstants.KubeDNSConfigMap, metav1.GetOptions{})
 	if err != nil && !apierrors.IsNotFound(err) {
 		return err
 	}
@@ -219,7 +224,7 @@ func createCoreDNSAddon(deploymentBytes, serviceBytes, configBytes []byte, clien
 	}
 
 	// Create the ConfigMap for CoreDNS or retain it in case it already exists
-	if err := apiclient.CreateOrRetainConfigMap(client, coreDNSConfigMap, kubeadmconstants.CoreDNS); err != nil {
+	if err := apiclient.CreateOrRetainConfigMap(client, coreDNSConfigMap, kubeadmconstants.CoreDNSConfigMap); err != nil {
 		return err
 	}
 

cmd/kubeadm/app/phases/addons/dns/dns_test.go

@@ -95,9 +95,11 @@ func TestCompileManifests(t *testing.T) {
 	}{
 		{
 			manifest: KubeDNSDeployment,
-			data: struct{ ImageRepository, Version, DNSBindAddr, DNSProbeAddr, DNSDomain, MasterTaintKey string }{
+			data: struct{ DeploymentName, KubeDNSImage, DNSMasqImage, SidecarImage, DNSBindAddr, DNSProbeAddr, DNSDomain, MasterTaintKey string }{
-				ImageRepository: "foo",
+				DeploymentName: "foo",
-				Version:         "foo",
+				KubeDNSImage:   "foo",
+				DNSMasqImage:   "foo",
+				SidecarImage:   "foo",
 				DNSBindAddr:    "foo",
 				DNSProbeAddr:   "foo",
 				DNSDomain:      "foo",
@@ -114,10 +116,10 @@ func TestCompileManifests(t *testing.T) {
 		},
 		{
 			manifest: CoreDNSDeployment,
-			data: struct{ ImageRepository, MasterTaintKey, Version string }{
+			data: struct{ DeploymentName, Image, MasterTaintKey string }{
-				ImageRepository: "foo",
+				DeploymentName: "foo",
+				Image:          "foo",
 				MasterTaintKey: "foo",
-				Version:         "foo",
 			},
 			expected: true,
 		},

cmd/kubeadm/app/phases/addons/dns/manifests.go

@@ -22,7 +22,7 @@ const (
 apiVersion: apps/v1
 kind: Deployment
 metadata:
-  name: kube-dns
+  name: {{ .DeploymentName }}
   namespace: kube-system
   labels:
     k8s-app: kube-dns
@@ -50,7 +50,7 @@ spec:
           optional: true
       containers:
       - name: kubedns
-        image: {{ .ImageRepository }}/k8s-dns-kube-dns:{{ .Version }}
+        image: {{ .KubeDNSImage }}
         imagePullPolicy: IfNotPresent
         resources:
           # TODO: Set memory limits when we've profiled the container for large
@@ -102,7 +102,7 @@ spec:
         - name: kube-dns-config
           mountPath: /kube-dns-config
       - name: dnsmasq
-        image: {{ .ImageRepository }}/k8s-dns-dnsmasq-nanny:{{ .Version }}
+        image: {{ .DNSMasqImage }}
         imagePullPolicy: IfNotPresent
         livenessProbe:
           httpGet:
@@ -143,7 +143,7 @@ spec:
         - name: kube-dns-config
           mountPath: /etc/k8s/dns/dnsmasq-nanny
       - name: sidecar
-        image: {{ .ImageRepository }}/k8s-dns-sidecar:{{ .Version }}
+        image: {{ .SidecarImage }}
         imagePullPolicy: IfNotPresent
         livenessProbe:
           httpGet:
@@ -213,7 +213,7 @@ spec:
 apiVersion: apps/v1
 kind: Deployment
 metadata:
-  name: coredns
+  name: {{ .DeploymentName }}
   namespace: kube-system
   labels:
     k8s-app: kube-dns
@@ -239,7 +239,7 @@ spec:
         effect: NoSchedule
       containers:
       - name: coredns
-        image: {{ .ImageRepository }}/coredns:{{ .Version }}
+        image: {{ .Image }}
         imagePullPolicy: IfNotPresent
         resources:
           limits:

cmd/kubeadm/app/phases/addons/proxy/proxy.go

@@ -21,7 +21,6 @@ import (
 	"fmt"
 
 	"github.com/pkg/errors"
-
 	apps "k8s.io/api/apps/v1"
 	"k8s.io/api/core/v1"
 	rbac "k8s.io/api/rbac/v1"
@@ -82,7 +81,7 @@ func EnsureProxyAddon(cfg *kubeadmapi.InitConfiguration, client clientset.Interf
 		return errors.Wrap(err, "error when parsing kube-proxy configmap template")
 	}
 	proxyDaemonSetBytes, err = kubeadmutil.ParseTemplate(KubeProxyDaemonSet19, struct{ Image, ProxyConfigMap, ProxyConfigMapKey string }{
-		Image:             images.GetKubeControlPlaneImage(constants.KubeProxy, &cfg.ClusterConfiguration),
+		Image:             images.GetKubernetesImage(constants.KubeProxy, &cfg.ClusterConfiguration),
 		ProxyConfigMap:    constants.KubeProxyConfigMap,
 		ProxyConfigMapKey: constants.KubeProxyConfigMapKey,
 	})

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

@@ -25,10 +25,9 @@ import (
 	"strings"
 
 	"github.com/pkg/errors"
-	"k8s.io/klog"
-
 	"k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/util/version"
+	"k8s.io/klog"
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmapiv1beta1 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1"
 	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
@@ -56,7 +55,7 @@ func GetStaticPodSpecs(cfg *kubeadmapi.InitConfiguration, k8sVersion *version.Ve
 	staticPodSpecs := map[string]v1.Pod{
 		kubeadmconstants.KubeAPIServer: staticpodutil.ComponentPod(v1.Container{
 			Name:            kubeadmconstants.KubeAPIServer,
-			Image:           images.GetKubeControlPlaneImage(kubeadmconstants.KubeAPIServer, &cfg.ClusterConfiguration),
+			Image:           images.GetKubernetesImage(kubeadmconstants.KubeAPIServer, &cfg.ClusterConfiguration),
 			ImagePullPolicy: v1.PullIfNotPresent,
 			Command:         getAPIServerCommand(cfg),
 			VolumeMounts:    staticpodutil.VolumeMountMapToSlice(mounts.GetVolumeMounts(kubeadmconstants.KubeAPIServer)),
@@ -66,7 +65,7 @@ func GetStaticPodSpecs(cfg *kubeadmapi.InitConfiguration, k8sVersion *version.Ve
 		}, mounts.GetVolumes(kubeadmconstants.KubeAPIServer)),
 		kubeadmconstants.KubeControllerManager: staticpodutil.ComponentPod(v1.Container{
 			Name:            kubeadmconstants.KubeControllerManager,
-			Image:           images.GetKubeControlPlaneImage(kubeadmconstants.KubeControllerManager, &cfg.ClusterConfiguration),
+			Image:           images.GetKubernetesImage(kubeadmconstants.KubeControllerManager, &cfg.ClusterConfiguration),
 			ImagePullPolicy: v1.PullIfNotPresent,
 			Command:         getControllerManagerCommand(cfg, k8sVersion),
 			VolumeMounts:    staticpodutil.VolumeMountMapToSlice(mounts.GetVolumeMounts(kubeadmconstants.KubeControllerManager)),
@@ -76,7 +75,7 @@ func GetStaticPodSpecs(cfg *kubeadmapi.InitConfiguration, k8sVersion *version.Ve
 		}, mounts.GetVolumes(kubeadmconstants.KubeControllerManager)),
 		kubeadmconstants.KubeScheduler: staticpodutil.ComponentPod(v1.Container{
 			Name:            kubeadmconstants.KubeScheduler,
-			Image:           images.GetKubeControlPlaneImage(kubeadmconstants.KubeScheduler, &cfg.ClusterConfiguration),
+			Image:           images.GetKubernetesImage(kubeadmconstants.KubeScheduler, &cfg.ClusterConfiguration),
 			ImagePullPolicy: v1.PullIfNotPresent,
 			Command:         getSchedulerCommand(cfg),
 			VolumeMounts:    staticpodutil.VolumeMountMapToSlice(mounts.GetVolumeMounts(kubeadmconstants.KubeScheduler)),

cmd/kubeadm/app/phases/etcd/local_test.go

@@ -38,7 +38,6 @@ func TestGetEtcdPodSpec(t *testing.T) {
 			Etcd: kubeadmapi.Etcd{
 				Local: &kubeadmapi.LocalEtcd{
 					DataDir: "/var/lib/etcd",
-					Image:   "",
 				},
 			},
 		},
@@ -69,7 +68,6 @@ func TestCreateLocalEtcdStaticPodManifestFile(t *testing.T) {
 					Etcd: kubeadmapi.Etcd{
 						Local: &kubeadmapi.LocalEtcd{
 							DataDir: "/var/lib/etcd",
-							Image:   "k8s.gcr.io/etcd",
 						},
 					},
 				},

cmd/kubeadm/app/phases/upgrade/BUILD

@@ -17,7 +17,6 @@ go_library(
         "//cmd/kubeadm/app/apis/kubeadm:go_default_library",
         "//cmd/kubeadm/app/apis/kubeadm/v1beta1: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/addons/dns:go_default_library",
         "//cmd/kubeadm/app/phases/addons/proxy:go_default_library",

cmd/kubeadm/app/phases/upgrade/compute.go

@@ -22,8 +22,8 @@ import (
 
 	versionutil "k8s.io/apimachinery/pkg/util/version"
 	clientset "k8s.io/client-go/kubernetes"
+	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/addons/dns"
 	etcdutil "k8s.io/kubernetes/cmd/kubeadm/app/util/etcd"
 )
@@ -56,20 +56,12 @@ func (u *Upgrade) CanUpgradeEtcd() bool {
 	return u.Before.EtcdVersion != u.After.EtcdVersion
 }
 
-// ActiveDNSAddon returns the version of CoreDNS or kube-dns
-func ActiveDNSAddon(featureGates map[string]bool) string {
-	if features.Enabled(featureGates, features.CoreDNS) {
-		return kubeadmconstants.CoreDNS
-	}
-	return kubeadmconstants.KubeDNS
-}
-
 // ClusterState describes the state of certain versions for a cluster
 type ClusterState struct {
 	// KubeVersion describes the version of the Kubernetes API Server, Controller Manager, Scheduler and Proxy.
 	KubeVersion string
 	// DNSType
-	DNSType string
+	DNSType kubeadmapi.DNSAddOnType
 	// DNSVersion describes the version of the kube-dns images used and manifest version
 	DNSVersion string
 	// KubeadmVersion describes the version of the kubeadm CLI
@@ -82,7 +74,7 @@ type ClusterState struct {
 
 // GetAvailableUpgrades fetches all versions from the specified VersionGetter and computes which
 // kinds of upgrades can be performed
-func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesAllowed, rcUpgradesAllowed bool, etcdClient etcdutil.ClusterInterrogator, featureGates map[string]bool, client clientset.Interface) ([]Upgrade, error) {
+func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesAllowed, rcUpgradesAllowed bool, etcdClient etcdutil.ClusterInterrogator, dnsType kubeadmapi.DNSAddOnType, client clientset.Interface) ([]Upgrade, error) {
 	fmt.Println("[upgrade] Fetching available versions to upgrade to")
 
 	// Collect the upgrades kubeadm can do in this list
@@ -120,7 +112,7 @@ func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesA
 		return upgrades, err
 	}
 
-	dnsType, dnsVersion, err := dns.DeployedDNSAddon(client)
+	currentDNSType, dnsVersion, err := dns.DeployedDNSAddon(client)
 	if err != nil {
 		return nil, err
 	}
@@ -128,7 +120,7 @@ func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesA
 	// Construct a descriptor for the current state of the world
 	beforeState := ClusterState{
 		KubeVersion:     clusterVersionStr,
-		DNSType:         dnsType,
+		DNSType:         currentDNSType,
 		DNSVersion:      dnsVersion,
 		KubeadmVersion:  kubeadmVersionStr,
 		KubeletVersions: kubeletVersions,
@@ -172,8 +164,8 @@ func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesA
 					Before:      beforeState,
 					After: ClusterState{
 						KubeVersion:    patchVersionStr,
-						DNSType:        ActiveDNSAddon(featureGates),
+						DNSType:        dnsType,
-						DNSVersion:     kubeadmconstants.GetDNSVersion(ActiveDNSAddon(featureGates)),
+						DNSVersion:     kubeadmconstants.GetDNSVersion(dnsType),
 						KubeadmVersion: newKubeadmVer,
 						EtcdVersion:    getSuggestedEtcdVersion(patchVersionStr),
 						// KubeletVersions is unset here as it is not used anywhere in .After
@@ -189,8 +181,8 @@ func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesA
 			Before:      beforeState,
 			After: ClusterState{
 				KubeVersion:    stableVersionStr,
-				DNSType:        ActiveDNSAddon(featureGates),
+				DNSType:        dnsType,
-				DNSVersion:     kubeadmconstants.GetDNSVersion(ActiveDNSAddon(featureGates)),
+				DNSVersion:     kubeadmconstants.GetDNSVersion(dnsType),
 				KubeadmVersion: stableVersionStr,
 				EtcdVersion:    getSuggestedEtcdVersion(stableVersionStr),
 				// KubeletVersions is unset here as it is not used anywhere in .After
@@ -235,8 +227,8 @@ func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesA
 				Before:      beforeState,
 				After: ClusterState{
 					KubeVersion:    previousBranchLatestVersionStr,
-					DNSType:        ActiveDNSAddon(featureGates),
+					DNSType:        dnsType,
-					DNSVersion:     kubeadmconstants.GetDNSVersion(ActiveDNSAddon(featureGates)),
+					DNSVersion:     kubeadmconstants.GetDNSVersion(dnsType),
 					KubeadmVersion: previousBranchLatestVersionStr,
 					EtcdVersion:    getSuggestedEtcdVersion(previousBranchLatestVersionStr),
 					// KubeletVersions is unset here as it is not used anywhere in .After
@@ -249,12 +241,12 @@ func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesA
 
 			// Default to assume that the experimental version to show is the unstable one
 			unstableKubeVersion := latestVersionStr
-			unstableKubeDNSVersion := kubeadmconstants.GetDNSVersion(ActiveDNSAddon(featureGates))
+			unstableKubeDNSVersion := kubeadmconstants.GetDNSVersion(dnsType)
 
 			// Ẃe should not display alpha.0. The previous branch's beta/rc versions are more relevant due how the kube branching process works.
 			if latestVersion.PreRelease() == "alpha.0" {
 				unstableKubeVersion = previousBranchLatestVersionStr
-				unstableKubeDNSVersion = kubeadmconstants.GetDNSVersion(ActiveDNSAddon(featureGates))
+				unstableKubeDNSVersion = kubeadmconstants.GetDNSVersion(dnsType)
 			}
 
 			upgrades = append(upgrades, Upgrade{
@@ -262,7 +254,7 @@ func GetAvailableUpgrades(versionGetterImpl VersionGetter, experimentalUpgradesA
 				Before:      beforeState,
 				After: ClusterState{
 					KubeVersion:    unstableKubeVersion,
-					DNSType:        ActiveDNSAddon(featureGates),
+					DNSType:        dnsType,
 					DNSVersion:     unstableKubeDNSVersion,
 					KubeadmVersion: unstableKubeVersion,
 					EtcdVersion:    getSuggestedEtcdVersion(unstableKubeVersion),

cmd/kubeadm/app/phases/upgrade/compute_test.go

@@ -24,12 +24,12 @@ import (
 
 	"github.com/coreos/etcd/clientv3"
 	"github.com/pkg/errors"
-
 	apps "k8s.io/api/apps/v1"
 	"k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	versionutil "k8s.io/apimachinery/pkg/util/version"
 	clientsetfake "k8s.io/client-go/kubernetes/fake"
+	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
 	etcdutil "k8s.io/kubernetes/cmd/kubeadm/app/util/etcd"
 )
@@ -124,9 +124,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 		allowExperimental, allowRCs bool
 		errExpected                 bool
 		etcdClient                  etcdutil.ClusterInterrogator
-		beforeDNSType               string
+		beforeDNSType               kubeadmapi.DNSAddOnType
 		beforeDNSVersion            string
-		featureGates                map[string]bool
+		dnsType                     kubeadmapi.DNSAddOnType
 	}{
 		{
 			name: "no action needed, already up-to-date",
@@ -138,9 +138,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stablePatchVersion: "v1.10.3",
 				stableVersion:      "v1.10.3",
 			},
-			beforeDNSType:     constants.CoreDNS,
+			beforeDNSType:     kubeadmapi.CoreDNS,
 			beforeDNSVersion:  "v1.0.6",
-			featureGates:      make(map[string]bool),
+			dnsType:           kubeadmapi.CoreDNS,
 			expectedUpgrades:  []Upgrade{},
 			allowExperimental: false,
 			errExpected:       false,
@@ -156,9 +156,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stablePatchVersion: "v1.10.3",
 				stableVersion:      "v1.10.3",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "version in the v1.10 series",
@@ -168,14 +168,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.1": 1,
 						},
 						KubeadmVersion: "v1.10.2",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.10.3",
 						KubeadmVersion: "v1.10.3",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.1.12",
 					},
@@ -195,9 +195,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stablePatchVersion: "v1.10.3",
 				stableVersion:      "v1.10.3",
 			}, ""),
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "version in the v1.10 series",
@@ -207,14 +207,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.1": 1,
 						},
 						KubeadmVersion: "v1.10.2",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.10.3",
 						KubeadmVersion: "v1.10.3",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.1.12",
 					},
@@ -234,9 +234,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stablePatchVersion: "v1.10.1",
 				stableVersion:      "v1.11.0",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "stable version",
@@ -246,14 +246,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.1": 1,
 						},
 						KubeadmVersion: "v1.11.0",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.11.0",
 						KubeadmVersion: "v1.11.0",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -273,9 +273,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stablePatchVersion: "v1.10.5",
 				stableVersion:      "v1.11.1",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "version in the v1.10 series",
@@ -285,14 +285,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.3": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.10.5",
 						KubeadmVersion: "v1.10.5", // Note: The kubeadm version mustn't be "downgraded" here
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.1.12",
 					},
@@ -305,14 +305,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.3": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.11.1",
 						KubeadmVersion: "v1.11.1",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -333,9 +333,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stableVersion:      "v1.10.5",
 				latestVersion:      "v1.11.0-alpha.2",
 			},
-			beforeDNSType:     constants.CoreDNS,
+			beforeDNSType:     kubeadmapi.CoreDNS,
 			beforeDNSVersion:  "v1.0.6",
-			featureGates:      make(map[string]bool),
+			dnsType:           kubeadmapi.CoreDNS,
 			expectedUpgrades:  []Upgrade{},
 			allowExperimental: true,
 			errExpected:       false,
@@ -352,9 +352,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stableVersion:      "v1.10.5",
 				latestVersion:      "v1.11.0-alpha.2",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "experimental version",
@@ -364,14 +364,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.5": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.11.0-alpha.2",
 						KubeadmVersion: "v1.11.0-alpha.2",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -392,9 +392,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stableVersion:      "v1.10.5",
 				latestVersion:      "v1.11.0-alpha.2",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "experimental version",
@@ -404,14 +404,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.5": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.11.0-alpha.2",
 						KubeadmVersion: "v1.11.0-alpha.2",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -433,9 +433,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				latestDevBranchVersion: "v1.11.0-beta.1",
 				latestVersion:          "v1.12.0-alpha.0",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "experimental version",
@@ -445,14 +445,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.5": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.11.0-beta.1",
 						KubeadmVersion: "v1.11.0-beta.1",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -474,9 +474,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				latestDevBranchVersion: "v1.11.0-rc.1",
 				latestVersion:          "v1.12.0-alpha.1",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "release candidate version",
@@ -486,14 +486,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.5": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.11.0-rc.1",
 						KubeadmVersion: "v1.11.0-rc.1",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -515,9 +515,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				latestDevBranchVersion: "v1.11.6-rc.1",
 				latestVersion:          "v1.12.1-alpha.0",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "experimental version", // Note that this is considered an experimental version in this uncommon scenario
@@ -527,14 +527,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.5": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.11.6-rc.1",
 						KubeadmVersion: "v1.11.6-rc.1",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -556,9 +556,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				latestDevBranchVersion: "v1.11.0-rc.1",
 				latestVersion:          "v1.12.0-alpha.2",
 			},
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "release candidate version",
@@ -568,14 +568,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.5": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.11.0-rc.1",
 						KubeadmVersion: "v1.11.0-rc.1",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.18",
 					},
@@ -588,14 +588,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.10.5": 1,
 						},
 						KubeadmVersion: "v1.10.5",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.12.0-alpha.2",
 						KubeadmVersion: "v1.12.0-alpha.2",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.24",
 					},
@@ -629,9 +629,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				kubeadmVersion: "v1.11.1",
 			}, "v1.12.1"),
 			etcdClient:       etcdClient,
-			beforeDNSType:    constants.CoreDNS,
+			beforeDNSType:    kubeadmapi.CoreDNS,
 			beforeDNSVersion: "1.0.6",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "version in the v1.11 series",
@@ -641,14 +641,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.11.0": 1,
 						},
 						KubeadmVersion: "v1.11.1",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.0.6",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.12.1",
 						KubeadmVersion: "v1.12.1",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.24",
 					},
@@ -666,9 +666,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stableVersion:      "v1.12.0",
 			},
 			etcdClient:       etcdClient,
-			beforeDNSType:    constants.KubeDNS,
+			beforeDNSType:    kubeadmapi.KubeDNS,
 			beforeDNSVersion: "1.14.7",
-			featureGates:     make(map[string]bool),
+			dnsType:          kubeadmapi.CoreDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "version in the v1.11 series",
@@ -678,14 +678,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.11.2": 1,
 						},
 						KubeadmVersion: "v1.12.0",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.7",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.12.0",
 						KubeadmVersion: "v1.12.0",
-						DNSType:        "coredns",
+						DNSType:        kubeadmapi.CoreDNS,
 						DNSVersion:     "1.2.6",
 						EtcdVersion:    "3.2.24",
 					},
@@ -703,9 +703,9 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				stableVersion:      "v1.12.0",
 			},
 			etcdClient:       etcdClient,
-			beforeDNSType:    constants.KubeDNS,
+			beforeDNSType:    kubeadmapi.KubeDNS,
 			beforeDNSVersion: "1.14.7",
-			featureGates:     map[string]bool{"CoreDNS": false},
+			dnsType:          kubeadmapi.KubeDNS,
 			expectedUpgrades: []Upgrade{
 				{
 					Description: "version in the v1.11 series",
@@ -715,14 +715,14 @@ func TestGetAvailableUpgrades(t *testing.T) {
 							"v1.11.2": 1,
 						},
 						KubeadmVersion: "v1.12.0",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.7",
 						EtcdVersion:    "3.1.12",
 					},
 					After: ClusterState{
 						KubeVersion:    "v1.12.0",
 						KubeadmVersion: "v1.12.0",
-						DNSType:        "kube-dns",
+						DNSType:        kubeadmapi.KubeDNS,
 						DNSVersion:     "1.14.13",
 						EtcdVersion:    "3.2.24",
 					},
@@ -736,13 +736,18 @@ func TestGetAvailableUpgrades(t *testing.T) {
 	for _, rt := range tests {
 		t.Run(rt.name, func(t *testing.T) {
 
+			dnsName := constants.CoreDNSDeploymentName
+			if rt.beforeDNSType == kubeadmapi.KubeDNS {
+				dnsName = constants.KubeDNSDeploymentName
+			}
+
 			client := clientsetfake.NewSimpleClientset(&apps.Deployment{
 				TypeMeta: metav1.TypeMeta{
 					Kind:       "Deployment",
 					APIVersion: "apps/v1",
 				},
 				ObjectMeta: metav1.ObjectMeta{
-					Name:      rt.beforeDNSType,
+					Name:      dnsName,
 					Namespace: "kube-system",
 					Labels: map[string]string{
 						"k8s-app": "kube-dns",
@@ -761,7 +766,7 @@ func TestGetAvailableUpgrades(t *testing.T) {
 				},
 			})
 
-			actualUpgrades, actualErr := GetAvailableUpgrades(rt.vg, rt.allowExperimental, rt.allowRCs, rt.etcdClient, rt.featureGates, client)
+			actualUpgrades, actualErr := GetAvailableUpgrades(rt.vg, rt.allowExperimental, rt.allowRCs, rt.etcdClient, rt.dnsType, client)
 			if !reflect.DeepEqual(actualUpgrades, rt.expectedUpgrades) {
 				t.Errorf("failed TestGetAvailableUpgrades\n\texpected upgrades: %v\n\tgot: %v", rt.expectedUpgrades, actualUpgrades)
 			}

cmd/kubeadm/app/phases/upgrade/postupgrade.go

@@ -24,7 +24,6 @@ import (
 	"time"
 
 	pkgerrors "github.com/pkg/errors"
-
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/util/errors"
@@ -34,7 +33,6 @@ import (
 	kubeadmapi "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm"
 	kubeadmapiv1beta1 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta1"
 	kubeadmconstants "k8s.io/kubernetes/cmd/kubeadm/app/constants"
-	"k8s.io/kubernetes/cmd/kubeadm/app/features"
 	"k8s.io/kubernetes/cmd/kubeadm/app/phases/addons/dns"
 	"k8s.io/kubernetes/cmd/kubeadm/app/phases/addons/proxy"
 	"k8s.io/kubernetes/cmd/kubeadm/app/phases/bootstraptoken/clusterinfo"
@@ -125,12 +123,12 @@ func PerformPostUpgradeTasks(client clientset.Interface, cfg *kubeadmapi.InitCon
 
 func removeOldDNSDeploymentIfAnotherDNSIsUsed(cfg *kubeadmapi.InitConfiguration, client clientset.Interface, dryRun bool) error {
 	return apiclient.TryRunCommand(func() error {
-		installedDeploymentName := kubeadmconstants.KubeDNS
+		installedDeploymentName := kubeadmconstants.KubeDNSDeploymentName
-		deploymentToDelete := kubeadmconstants.CoreDNS
+		deploymentToDelete := kubeadmconstants.CoreDNSDeploymentName
 
-		if features.Enabled(cfg.FeatureGates, features.CoreDNS) {
+		if cfg.DNS.Type == kubeadmapi.CoreDNS {
-			installedDeploymentName = kubeadmconstants.CoreDNS
+			installedDeploymentName = kubeadmconstants.CoreDNSDeploymentName
-			deploymentToDelete = kubeadmconstants.KubeDNS
+			deploymentToDelete = kubeadmconstants.KubeDNSDeploymentName
 		}
 
 		// If we're dry-running, we don't need to wait for the new DNS addon to become ready

cmd/kubeadm/app/phases/upgrade/prepull.go

@@ -21,7 +21,6 @@ import (
 	"time"
 
 	"github.com/pkg/errors"
-
 	apps "k8s.io/api/apps/v1"
 	"k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -65,7 +64,7 @@ func (d *DaemonSetPrepuller) CreateFunc(component string) error {
 	if component == constants.Etcd {
 		image = images.GetEtcdImage(d.cfg)
 	} else {
-		image = images.GetKubeControlPlaneImage(component, d.cfg)
+		image = images.GetKubernetesImage(component, d.cfg)
 	}
 	ds := buildPrePullDaemonSet(component, image)
 

cmd/kubeadm/app/util/config/testdata/conversion/master/internal.yaml

@@ -172,12 +172,17 @@ ControlPlaneEndpoint: ""
 ControllerManager:
   ExtraArgs: null
   ExtraVolumes: null
+DNS:
+  ImageRepository: ""
+  ImageTag: ""
+  Type: CoreDNS
 Etcd:
   External: null
   Local:
     DataDir: /var/lib/etcd
     ExtraArgs: null
-    Image: ""
+    ImageRepository: ""
+    ImageTag: ""
     PeerCertSANs: null
     ServerCertSANs: null
 FeatureGates: null

cmd/kubeadm/app/util/config/testdata/conversion/master/v1beta1.yaml

@@ -39,10 +39,11 @@ certificatesDir: /etc/kubernetes/pki
 clusterName: kubernetes
 controlPlaneEndpoint: ""
 controllerManager: {}
+dns:
+  type: CoreDNS
 etcd:
   local:
     dataDir: /var/lib/etcd
-    image: ""
 imageRepository: k8s.gcr.io
 kind: ClusterConfiguration
 kubernetesVersion: v1.11.2

cmd/kubeadm/app/util/config/testdata/defaulting/master/defaulted.yaml

@@ -29,10 +29,11 @@ certificatesDir: /var/lib/kubernetes/pki
 clusterName: kubernetes
 controlPlaneEndpoint: ""
 controllerManager: {}
+dns:
+  type: CoreDNS
 etcd:
   local:
     dataDir: /var/lib/etcd
-    image: ""
 imageRepository: my-company.com
 kind: ClusterConfiguration
 kubernetesVersion: v1.12.0