Conditionally use RBN or ip names in kops-controller

nodeup/pkg/model/kubelet.go

@@ -27,10 +27,10 @@ import (
 
 	"github.com/aws/aws-sdk-go/aws/ec2metadata"
 	"github.com/aws/aws-sdk-go/aws/session"
-	"github.com/aws/aws-sdk-go/service/ec2"
 
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/klog/v2"
+
 	"k8s.io/kops/pkg/apis/kops"
 	"k8s.io/kops/pkg/flagbuilder"
 	"k8s.io/kops/pkg/nodelabels"
@@ -59,7 +59,6 @@ var _ fi.ModelBuilder = &KubeletBuilder{}
 
 // Build is responsible for building the kubelet configuration
 func (b *KubeletBuilder) Build(c *fi.ModelBuilderContext) error {
-
 	err := b.buildKubeletServingCertificate(c)
 	if err != nil {
 		return fmt.Errorf("error building kubelet server cert: %v", err)
@@ -191,6 +190,8 @@ func (b *KubeletBuilder) buildSystemdEnvironmentFile(kubeletConfig *kops.Kubelet
 		kubeletConfig.BootstrapKubeconfig = ""
 	}
 
+	kubeletConfig.HostnameOverride = ""
+
 	// TODO: Dump the separate file for flags - just complexity!
 	flags, err := flagbuilder.BuildFlags(kubeletConfig)
 	if err != nil {
@@ -304,7 +305,6 @@ func (b *KubeletBuilder) buildSystemdService() *nodetasks.Service {
 	service.InitDefaults()
 
 	if b.ConfigurationMode == "Warming" {
-
 		service.Running = fi.Bool(false)
 	}
 
@@ -551,7 +551,6 @@ func (b *KubeletBuilder) buildMasterKubeletKubeconfig(c *fi.ModelBuilderContext)
 }
 
 func (b *KubeletBuilder) buildKubeletServingCertificate(c *fi.ModelBuilderContext) error {
-
 	if b.UseKopsControllerForNodeBootstrap() {
 		name := "kubelet-server"
 		dir := b.PathSrvKubernetes()
@@ -599,29 +598,15 @@ func (b *KubeletBuilder) buildKubeletServingCertificate(c *fi.ModelBuilderContex
 		}
 	}
 	return nil
-
 }
 
 func (b *KubeletBuilder) kubeletNames() ([]string, error) {
-	if kops.CloudProviderID(b.Cluster.Spec.CloudProvider) != kops.CloudProviderAWS {
-		name, err := os.Hostname()
-		if err != nil {
-			return nil, err
-		}
-
-		addrs, _ := net.LookupHost(name)
-
-		return append(addrs, name), nil
-	}
-
-	cloud := b.Cloud.(awsup.AWSCloud)
-
-	result, err := cloud.EC2().DescribeInstances(&ec2.DescribeInstancesInput{
-		InstanceIds: []*string{&b.InstanceID},
-	})
+	name, err := os.Hostname()
 	if err != nil {
-		return nil, fmt.Errorf("error describing instances: %v", err)
+		return nil, err
 	}
 
-	return awsup.GetInstanceCertificateNames(result)
+	addrs, _ := net.LookupHost(name)
+
+	return append(addrs, name), nil
 }

upup/pkg/fi/cloudup/awsup/aws_cloud.go

@@ -51,6 +51,8 @@ import (
 
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/util/sets"
+	k8s_aws "k8s.io/legacy-cloud-providers/aws"
+
 	"k8s.io/kops/dnsprovider/pkg/dnsprovider"
 	dnsproviderroute53 "k8s.io/kops/dnsprovider/pkg/dnsprovider/providers/aws/route53"
 	"k8s.io/kops/pkg/apis/kops"
@@ -60,7 +62,6 @@ import (
 	identity_aws "k8s.io/kops/pkg/nodeidentity/aws"
 	"k8s.io/kops/pkg/resources/spotinst"
 	"k8s.io/kops/upup/pkg/fi"
-	k8s_aws "k8s.io/legacy-cloud-providers/aws"
 )
 
 // By default, aws-sdk-go only retries 3 times, which doesn't give
@@ -69,21 +70,29 @@ import (
 // backoff along the way.
 const ClientMaxRetries = 13
 
-const DescribeTagsMaxAttempts = 120
-const DescribeTagsRetryInterval = 2 * time.Second
-const DescribeTagsLogInterval = 10 // this is in "retry intervals"
+const (
+	DescribeTagsMaxAttempts   = 120
+	DescribeTagsRetryInterval = 2 * time.Second
+	DescribeTagsLogInterval   = 10 // this is in "retry intervals"
+)
 
-const CreateTagsMaxAttempts = 120
-const CreateTagsRetryInterval = 2 * time.Second
-const CreateTagsLogInterval = 10 // this is in "retry intervals"
+const (
+	CreateTagsMaxAttempts   = 120
+	CreateTagsRetryInterval = 2 * time.Second
+	CreateTagsLogInterval   = 10 // this is in "retry intervals"
+)
 
-const DeleteTagsMaxAttempts = 120
-const DeleteTagsRetryInterval = 2 * time.Second
-const DeleteTagsLogInterval = 10 // this is in "retry intervals"
+const (
+	DeleteTagsMaxAttempts   = 120
+	DeleteTagsRetryInterval = 2 * time.Second
+	DeleteTagsLogInterval   = 10 // this is in "retry intervals"
+)
 
-const TagClusterName = "KubernetesCluster"
-const TagNameRolePrefix = "k8s.io/role/"
-const TagNameEtcdClusterPrefix = "k8s.io/etcd/"
+const (
+	TagClusterName           = "KubernetesCluster"
+	TagNameRolePrefix        = "k8s.io/role/"
+	TagNameEtcdClusterPrefix = "k8s.io/etcd/"
+)
 
 const TagRoleMaster = "master"
 
@@ -382,7 +391,6 @@ func NewAWSCloud(region string, tags map[string]string) (AWSCloud, error) {
 }
 
 func (c *awsCloudImplementation) addHandlers(regionName string, h *request.Handlers) {
-
 	delayer := c.getCrossRequestRetryDelay(regionName)
 	if delayer != nil {
 		h.Sign.PushFrontNamed(request.NamedHandler{
@@ -650,7 +658,6 @@ func getCloudGroups(c AWSCloud, cluster *kops.Cluster, instancegroups []*kops.In
 	}
 
 	return groups, nil
-
 }
 
 // FindAutoscalingGroups finds autoscaling groups matching the specified tags
@@ -715,7 +722,6 @@ func FindAutoscalingGroups(c AWSCloud, tags map[string]string) ([]*autoscaling.G
 				return nil, fmt.Errorf("error listing autoscaling groups: %v", err)
 			}
 		}
-
 	}
 
 	return asgs, nil
@@ -771,7 +777,7 @@ func findAutoscalingGroupLaunchConfiguration(c AWSCloud, g *autoscaling.Group) (
 	}
 
 	version := aws.StringValue(launchTemplate.Version)
-	//Correctly Handle Default and Latest Versions
+	// Correctly Handle Default and Latest Versions
 	klog.V(4).Infof("Launch Template Version Specified By ASG: %v", version)
 	if version == "" || version == "$Default" || version == "$Latest" {
 		input := &ec2.DescribeLaunchTemplatesInput{
@@ -949,7 +955,6 @@ func findInstances(c AWSCloud, ig *kops.InstanceGroup) (map[string]*ec2.Instance
 		}
 	}
 	return instances, nil
-
 }
 
 func findDetachedInstances(c AWSCloud, g *autoscaling.Group) ([]*string, error) {
@@ -1316,6 +1321,7 @@ func removeELBTags(c AWSCloud, loadBalancerName string, tags map[string]string)
 
 	return nil
 }
+
 func (c *awsCloudImplementation) RemoveELBV2Tags(ResourceArn string, tags map[string]string) error {
 	return removeELBV2Tags(c, ResourceArn, tags)
 }
@@ -2082,10 +2088,16 @@ func GetInstanceCertificateNames(instances *ec2.DescribeInstancesOutput) (addrs
 	}
 
 	instance := instances.Reservations[0].Instances[0]
+	{
+		if *instance.PrivateDnsNameOptions.HostnameType == ec2.HostnameTypeResourceName {
+			name := *instance.InstanceId
+			addrs = append(addrs, name)
+		} else {
+			name := *instance.PrivateDnsName
+			addrs = append(addrs, name)
 
-	name := *instance.PrivateDnsName
-
-	addrs = append(addrs, name)
+		}
+	}
 
 	// We only use data for the first interface, and only the first IP
 	for _, iface := range instance.NetworkInterfaces {

upup/pkg/fi/cloudup/awsup/aws_verifier.go

@@ -36,6 +36,7 @@ import (
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/ec2"
 	"github.com/aws/aws-sdk-go/service/sts"
+
 	"k8s.io/kops/pkg/bootstrap"
 	nodeidentityaws "k8s.io/kops/pkg/nodeidentity/aws"
 )

upup/pkg/fi/nodeup/command.go

@@ -484,7 +484,11 @@ func evaluateHostnameOverride(cloudProvider api.CloudProviderID) (string, error)
 		if err != nil {
 			return "", fmt.Errorf("error reading local-hostname from AWS metadata: %v", err)
 		}
-		return string(hostnameBytes), nil
+		hostname := string(hostnameBytes)
+		if strings.HasPrefix(hostname, "i-") {
+			return "", nil
+		}
+		return hostname, nil
 	case api.CloudProviderGCE:
 		// This lets us tolerate broken hostnames (i.e. systemd)
 		b, err := vfs.Context.ReadFile("metadata://gce/instance/hostname")