Make it possible to set node naming convention

As of k8s 1.23, CCM supports both instance ID (resource name) and private dns (ip name) based naming. It is not possible for karpenter to determine when which convention is used, and this may also depend on the installer used. Therefore this is added as a CLI argument Update pkg/utils/options/options.go Co-authored-by: Ellis Tarn <[email protected]>
aws · Dec 16, 2021 · c1df256 · c1df256
1 parent b405f79
commit c1df256
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Showing 3 changed files with 27 additions and 12 deletions.
diff --git a/pkg/cloudprovider/aws/instance.go b/pkg/cloudprovider/aws/instance.go
@@ -33,6 +33,7 @@ import (
 	"github.com/aws/karpenter/pkg/apis/provisioning/v1alpha5"
 	"github.com/aws/karpenter/pkg/cloudprovider"
 	"github.com/aws/karpenter/pkg/cloudprovider/aws/apis/v1alpha1"
+	"github.com/aws/karpenter/pkg/utils/injection"
 )
 
 type InstanceProvider struct {
@@ -73,9 +74,8 @@ func (p *InstanceProvider) Create(ctx context.Context, constraints *v1alpha1.Con
 			aws.StringValue(instance.Placement.AvailabilityZone),
 			getCapacityType(instance),
 		)
-
 		// Convert Instance to Node
-		node, err := p.instanceToNode(instance, instanceTypes)
+		node, err := p.instanceToNode(ctx, instance, instanceTypes)
 		if err != nil {
 			logging.FromContext(ctx).Errorf("creating Node from an EC2 Instance: %s", err.Error())
 			continue
@@ -229,12 +229,16 @@ func (p *InstanceProvider) getInstances(ctx context.Context, ids []*string) ([]*
 	return instances, err
 }
 
-func (p *InstanceProvider) instanceToNode(instance *ec2.Instance, instanceTypes []cloudprovider.InstanceType) (*v1.Node, error) {
+func (p *InstanceProvider) instanceToNode(ctx context.Context, instance *ec2.Instance, instanceTypes []cloudprovider.InstanceType) (*v1.Node, error) {
 	for _, instanceType := range instanceTypes {
 		if instanceType.Name() == aws.StringValue(instance.InstanceType) {
+			nodeName := strings.ToLower(aws.StringValue(instance.PrivateDnsName))
+			if injection.GetOptions(ctx).AWSNodeNameConvention == "resource-name" {
+				nodeName = aws.StringValue(instance.InstanceId)
+			}
 			return &v1.Node{
 				ObjectMeta: metav1.ObjectMeta{
-					Name: aws.StringValue(instance.PrivateDnsName),
+					Name: nodeName,
 					Labels: map[string]string{
 						v1.LabelTopologyZone:       aws.StringValue(instance.Placement.AvailabilityZone),
 						v1.LabelInstanceTypeStable: aws.StringValue(instance.InstanceType),

diff --git a/pkg/cloudprovider/aws/suite_test.go b/pkg/cloudprovider/aws/suite_test.go
@@ -64,7 +64,13 @@ func TestAPIs(t *testing.T) {
 
 var _ = BeforeSuite(func() {
 	env = test.NewEnvironment(ctx, func(e *test.Environment) {
-		ctx = injection.WithOptions(ctx, options.Options{ClusterName: "test-cluster", ClusterEndpoint: "https://test-cluster"})
+		opts := options.Options{
+			ClusterName:           "test-cluster",
+			ClusterEndpoint:       "https://test-cluster",
+			AWSNodeNameConvention: "ip-name",
+		}
+		Expect(opts.Validate()).To(Succeed(), "Failed to validate options")
+		ctx = injection.WithOptions(ctx, opts)
 		launchTemplateCache = cache.New(CacheTTL, CacheCleanupInterval)
 		unavailableOfferingsCache = cache.New(InsufficientCapacityErrorCacheTTL, InsufficientCapacityErrorCacheCleanupInterval)
 		fakeEC2API = &fake.EC2API{}

diff --git a/pkg/utils/options/options.go b/pkg/utils/options/options.go
@@ -32,6 +32,7 @@ func MustParse() Options {
 	flag.IntVar(&opts.WebhookPort, "port", 8443, "The port the webhook endpoint binds to for validation and mutation of resources")
 	flag.IntVar(&opts.KubeClientQPS, "kube-client-qps", env.WithDefaultInt("KUBE_CLIENT_QPS", 200), "The smoothed rate of qps to kube-apiserver")
 	flag.IntVar(&opts.KubeClientBurst, "kube-client-burst", env.WithDefaultInt("KUBE_CLIENT_BURST", 300), "The maximum allowed burst of queries to the kube-apiserver")
+	flag.StringVar(&opts.AWSNodeNameConvention, "aws-node-name-convention", env.WithDefaultString("AWS_NODE_NAME_CONVENTION", "ip-name"), "The node naming convention used by the AWS cloud provider. DEPRECATION WARNING: this field may be deprecated at any time")
 	flag.Parse()
 	if err := opts.Validate(); err != nil {
 		panic(err)
@@ -41,20 +42,24 @@ func MustParse() Options {
 
 // Options for running this binary
 type Options struct {
-	ClusterName     string
-	ClusterEndpoint string
-	MetricsPort     int
-	HealthProbePort int
-	WebhookPort     int
-	KubeClientQPS   int
-	KubeClientBurst int
+	ClusterName           string
+	ClusterEndpoint       string
+	MetricsPort           int
+	HealthProbePort       int
+	WebhookPort           int
+	KubeClientQPS         int
+	KubeClientBurst       int
+	AWSNodeNameConvention string
 }
 
 func (o Options) Validate() (err error) {
 	err = multierr.Append(err, o.validateEndpoint())
 	if o.ClusterName == "" {
 		err = multierr.Append(err, fmt.Errorf("CLUSTER_NAME is required"))
 	}
+	if o.AWSNodeNameConvention != "ip-name" && o.AWSNodeNameConvention != "resource-name" {
+		err = multierr.Append(err, fmt.Errorf("aws-node-name-convention may only be either ip-name or resource-name"))
+	}
 	return err
 }