⚠️ Remove KubeadmConfig UseExperimentalRetryJoin

.golangci.yml

@@ -238,7 +238,7 @@ linters:
     # should be removed as the referenced deprecated item is removed from the project.
       - linters:
           - staticcheck
-        text: 'SA1019: (bootstrapv1.ClusterStatus|KubeadmConfigSpec.UseExperimentalRetryJoin|scope.Config.Spec.UseExperimentalRetryJoin|DockerMachine.Spec.Bootstrapped|machineStatus.Bootstrapped|dockerMachine.Spec.Backend.Docker.Bootstrapped|dockerMachine.Spec.Bootstrapped|devMachine.Spec.Backend.Docker.Bootstrapped|c.TopologyPlan|clusterv1.ClusterClassVariableMetadata|clusterv1beta1.ClusterClassVariableMetadata|(variable|currentDefinition|specVar|newVariableDefinition|statusVarDefinition).Metadata) is deprecated'
+        text: 'SA1019: (bootstrapv1.ClusterStatus|DockerMachine.Spec.Bootstrapped|machineStatus.Bootstrapped|dockerMachine.Spec.Backend.Docker.Bootstrapped|dockerMachine.Spec.Bootstrapped|devMachine.Spec.Backend.Docker.Bootstrapped|c.TopologyPlan|clusterv1.ClusterClassVariableMetadata|clusterv1beta1.ClusterClassVariableMetadata|(variable|currentDefinition|specVar|newVariableDefinition|statusVarDefinition).Metadata) is deprecated'
         # Deprecations for MD revision management
       - linters:
           - staticcheck

bootstrap/kubeadm/api/v1beta1/conversion.go

@@ -82,6 +82,11 @@ func Convert_v1beta2_KubeadmConfigStatus_To_v1beta1_KubeadmConfigStatus(in *boot
 	return nil
 }
 
+func Convert_v1beta1_KubeadmConfigSpec_To_v1beta2_KubeadmConfigSpec(in *KubeadmConfigSpec, out *bootstrapv1.KubeadmConfigSpec, s apimachineryconversion.Scope) error {
+	// NOTE: v1beta2 KubeadmConfigSpec does not have UseExperimentalRetryJoin anymore, so it's fine to just lose this field.
+	return autoConvert_v1beta1_KubeadmConfigSpec_To_v1beta2_KubeadmConfigSpec(in, out, s)
+}
+
 func Convert_v1beta1_KubeadmConfigStatus_To_v1beta2_KubeadmConfigStatus(in *KubeadmConfigStatus, out *bootstrapv1.KubeadmConfigStatus, s apimachineryconversion.Scope) error {
 	if err := autoConvert_v1beta1_KubeadmConfigStatus_To_v1beta2_KubeadmConfigStatus(in, out, s); err != nil {
 		return err

bootstrap/kubeadm/api/v1beta1/conversion_test.go

@@ -39,14 +39,16 @@ func TestFuzzyConversion(t *testing.T) {
 		FuzzerFuncs: []fuzzer.FuzzerFuncs{KubeadmConfigFuzzFuncs},
 	}))
 	t.Run("for KubeadmConfigTemplate", utilconversion.FuzzTestFunc(utilconversion.FuzzTestFuncInput{
-		Hub:   &bootstrapv1.KubeadmConfigTemplate{},
-		Spoke: &KubeadmConfigTemplate{},
+		Hub:         &bootstrapv1.KubeadmConfigTemplate{},
+		Spoke:       &KubeadmConfigTemplate{},
+		FuzzerFuncs: []fuzzer.FuzzerFuncs{KubeadmConfigTemplateFuzzFuncs},
 	}))
 }
 
 func KubeadmConfigFuzzFuncs(_ runtimeserializer.CodecFactory) []interface{} {
 	return []interface{}{
 		hubKubeadmConfigStatus,
+		spokeKubeadmConfigSpec,
 		spokeKubeadmConfigStatus,
 	}
 }
@@ -69,6 +71,13 @@ func hubKubeadmConfigStatus(in *bootstrapv1.KubeadmConfigStatus, c fuzz.Continue
 	}
 }
 
+func spokeKubeadmConfigSpec(in *KubeadmConfigSpec, c fuzz.Continue) {
+	c.FuzzNoCustom(in)
+
+	// Drop UseExperimentalRetryJoin as we intentionally don't preserve it.
+	in.UseExperimentalRetryJoin = false
+}
+
 func spokeKubeadmConfigStatus(in *KubeadmConfigStatus, c fuzz.Continue) {
 	c.FuzzNoCustom(in)
 	// Drop empty structs with only omit empty fields.
@@ -78,3 +87,9 @@ func spokeKubeadmConfigStatus(in *KubeadmConfigStatus, c fuzz.Continue) {
 		}
 	}
 }
+
+func KubeadmConfigTemplateFuzzFuncs(_ runtimeserializer.CodecFactory) []interface{} {
+	return []interface{}{
+		spokeKubeadmConfigSpec,
+	}
+}

bootstrap/kubeadm/api/v1beta2/kubeadmconfig_types.go

@@ -122,22 +122,6 @@ type KubeadmConfigSpec struct {
 	// +optional
 	Verbosity *int32 `json:"verbosity,omitempty"`
 
-	// useExperimentalRetryJoin replaces a basic kubeadm command with a shell
-	// script with retries for joins.
-	//
-	// This is meant to be an experimental temporary workaround on some environments
-	// where joins fail due to timing (and other issues). The long term goal is to add retries to
-	// kubeadm proper and use that functionality.
-	//
-	// This will add about 40KB to userdata
-	//
-	// For more information, refer to https://github.com/kubernetes-sigs/cluster-api/pull/2763#discussion_r397306055.
-	// +optional
-	//
-	// Deprecated: This experimental fix is no longer needed and this field will be removed in a future release.
-	// When removing also remove from staticcheck exclude-rules for SA1019 in golangci.yml
-	UseExperimentalRetryJoin bool `json:"useExperimentalRetryJoin,omitempty"`
-
 	// ignition contains Ignition specific configuration.
 	// +optional
 	Ignition *IgnitionSpec `json:"ignition,omitempty"`
@@ -347,16 +331,6 @@ func (c *KubeadmConfigSpec) validateIgnition(pathPrefix *field.Path) field.Error
 		}
 	}
 
-	if c.UseExperimentalRetryJoin {
-		allErrs = append(
-			allErrs,
-			field.Forbidden(
-				pathPrefix.Child("useExperimentalRetryJoin"),
-				cannotUseWithIgnition,
-			),
-		)
-	}
-
 	for i, file := range c.Files {
 		if file.Encoding == Gzip || file.Encoding == GzipBase64 {
 			allErrs = append(

bootstrap/kubeadm/internal/cloudinit/cloudinit.go

@@ -18,64 +18,49 @@ package cloudinit
 
 import (
 	"bytes"
-	_ "embed"
 	"fmt"
 	"text/template"
 
 	"github.com/blang/semver/v4"
 	"github.com/pkg/errors"
 
 	bootstrapv1 "sigs.k8s.io/cluster-api/bootstrap/kubeadm/api/v1beta2"
-	"sigs.k8s.io/cluster-api/util/version"
 )
 
 const (
 	standardJoinCommand = "kubeadm join --config /run/kubeadm/kubeadm-join-config.yaml %s"
 	// sentinelFileCommand writes a file to /run/cluster-api to signal successful Kubernetes bootstrapping in a way that
 	// works both for Linux and Windows OS.
-	sentinelFileCommand            = "echo success > /run/cluster-api/bootstrap-success.complete"
-	retriableJoinScriptName        = "/usr/local/bin/kubeadm-bootstrap-script"
-	retriableJoinScriptOwner       = "root"
-	retriableJoinScriptPermissions = "0755"
-	cloudConfigHeader              = `## template: jinja
+	sentinelFileCommand = "echo success > /run/cluster-api/bootstrap-success.complete"
+	cloudConfigHeader   = `## template: jinja
 #cloud-config
 `
 )
 
 // BaseUserData is shared across all the various types of files written to disk.
 type BaseUserData struct {
-	Header               string
-	BootCommands         []string
-	PreKubeadmCommands   []string
-	PostKubeadmCommands  []string
-	AdditionalFiles      []bootstrapv1.File
-	WriteFiles           []bootstrapv1.File
-	Users                []bootstrapv1.User
-	NTP                  *bootstrapv1.NTP
-	DiskSetup            *bootstrapv1.DiskSetup
-	Mounts               []bootstrapv1.MountPoints
-	ControlPlane         bool
-	UseExperimentalRetry bool
-	KubeadmCommand       string
-	KubeadmVerbosity     string
-	SentinelFileCommand  string
-	KubernetesVersion    semver.Version
+	Header              string
+	BootCommands        []string
+	PreKubeadmCommands  []string
+	PostKubeadmCommands []string
+	AdditionalFiles     []bootstrapv1.File
+	WriteFiles          []bootstrapv1.File
+	Users               []bootstrapv1.User
+	NTP                 *bootstrapv1.NTP
+	DiskSetup           *bootstrapv1.DiskSetup
+	Mounts              []bootstrapv1.MountPoints
+	ControlPlane        bool
+	KubeadmCommand      string
+	KubeadmVerbosity    string
+	SentinelFileCommand string
+	KubernetesVersion   semver.Version
 }
 
-func (input *BaseUserData) prepare() error {
+func (input *BaseUserData) prepare() {
 	input.Header = cloudConfigHeader
 	input.WriteFiles = append(input.WriteFiles, input.AdditionalFiles...)
 	input.KubeadmCommand = fmt.Sprintf(standardJoinCommand, input.KubeadmVerbosity)
-	if input.UseExperimentalRetry {
-		input.KubeadmCommand = retriableJoinScriptName
-		joinScriptFile, err := generateBootstrapScript(input, input.KubernetesVersion)
-		if err != nil {
-			return errors.Wrap(err, "failed to generate user data for machine joining control plane")
-		}
-		input.WriteFiles = append(input.WriteFiles, *joinScriptFile)
-	}
 	input.SentinelFileCommand = sentinelFileCommand
-	return nil
 }
 
 func generate(kind string, tpl string, data interface{}) ([]byte, error) {
@@ -124,36 +109,3 @@ func generate(kind string, tpl string, data interface{}) ([]byte, error) {
 
 	return out.Bytes(), nil
 }
-
-var (
-	//go:embed kubeadm-bootstrap-script-pre-k8s-1-31.sh
-	kubeadmBootstrapScriptPre1_31 string
-	//go:embed kubeadm-bootstrap-script.sh
-	kubeadmBootstrapScript string
-
-	// kubernetesVersion1_31 is the version where kubeadm removed the update-status phase
-	// and introduced new phases with the ControlPlaneKubeletLocalMode feature gate.
-	kubernetesVersion1_31 = semver.MustParse("1.31.0")
-)
-
-func generateBootstrapScript(input interface{}, parsedversion semver.Version) (*bootstrapv1.File, error) {
-	bootstrapScript := kubeadmBootstrapScript
-	if useKubeadmBootstrapScriptPre1_31(parsedversion) {
-		bootstrapScript = kubeadmBootstrapScriptPre1_31
-	}
-
-	joinScript, err := generate("JoinScript", bootstrapScript, input)
-	if err != nil {
-		return nil, errors.Wrap(err, "failed to bootstrap script for machine joins")
-	}
-	return &bootstrapv1.File{
-		Path:        retriableJoinScriptName,
-		Owner:       retriableJoinScriptOwner,
-		Permissions: retriableJoinScriptPermissions,
-		Content:     string(joinScript),
-	}, nil
-}
-
-func useKubeadmBootstrapScriptPre1_31(parsedversion semver.Version) bool {
-	return version.Compare(parsedversion, kubernetesVersion1_31, version.WithoutPreReleases()) < 0
-}