feat(eks): arm64 support (#9875)

feat(eks): support ARM64 for self-managed and managed nodegroup

Closes: #9915 

- [x] self-managed nodegroups with `ARM64` support
- [x] managed nodegroups with `ARM64` support
- [x] cluster default capacity with `ARM64` support
- [x] implicitly determine the `amiType` from the `instanceType` to make it just works.
- [x] update README
- [x] integ and unit tests

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk/aws-eks/README.md

@@ -176,6 +176,31 @@ cluster.addNodegroup('nodegroup', {
 });
 ```
 
+### ARM64 Support
+
+Instance types with `ARM64` architecture are supported in both managed nodegroup and self-managed capacity. Simply specify an ARM64 `instanceType` (such as `m6g.medium`), and the latest 
+Amazon Linux 2 AMI for ARM64 will be automatically selected.
+
+```ts
+// create a cluster with a default managed nodegroup 
+cluster = new eks.Cluster(this, 'Cluster', {
+  vpc,
+  mastersRole,
+  version: eks.KubernetesVersion.V1_17,
+});
+
+// add a managed ARM64 nodegroup
+cluster.addNodegroup('extra-ng-arm', {
+  instanceType: new ec2.InstanceType('m6g.medium'),
+  minSize: 2,
+});
+
+// add a self-managed ARM64 nodegroup
+cluster.addCapacity('self-ng-arm', {
+  instanceType: new ec2.InstanceType('m6g.medium'),
+  minCapacity: 2,
+})
+```
 
 ### Fargate
 

packages/@aws-cdk/aws-eks/lib/cluster.ts

@@ -12,6 +12,7 @@ import { AwsAuth } from './aws-auth';
 import { ClusterResource, clusterArnComponents } from './cluster-resource';
 import { FargateProfile, FargateProfileOptions } from './fargate-profile';
 import { HelmChart, HelmChartOptions } from './helm-chart';
+import { INSTANCE_TYPES } from './instance-types';
 import { KubernetesManifest } from './k8s-manifest';
 import { KubernetesObjectValue } from './k8s-object-value';
 import { KubernetesPatch } from './k8s-patch';
@@ -1047,6 +1048,7 @@ export class Cluster extends ClusterBase {
         new BottleRocketImage() :
         new EksOptimizedImage({
           nodeType: nodeTypeForInstanceType(options.instanceType),
+          cpuArch: cpuArchForInstanceType(options.instanceType),
           kubernetesVersion: this.version.version,
         }),
       updateType: options.updateType,
@@ -1639,6 +1641,13 @@ export interface EksOptimizedImageProps {
    */
   readonly nodeType?: NodeType;
 
+  /**
+   * What cpu architecture to retrieve the image for (arm64 or x86_64)
+   *
+   * @default CpuArch.X86_64
+   */
+  readonly cpuArch?: CpuArch;
+
   /**
    * The Kubernetes version to use
    *
@@ -1652,20 +1661,22 @@ export interface EksOptimizedImageProps {
  */
 export class EksOptimizedImage implements ec2.IMachineImage {
   private readonly nodeType?: NodeType;
+  private readonly cpuArch?: CpuArch;
   private readonly kubernetesVersion?: string;
-
   private readonly amiParameterName: string;
 
   /**
    * Constructs a new instance of the EcsOptimizedAmi class.
    */
   public constructor(props: EksOptimizedImageProps = {}) {
     this.nodeType = props.nodeType ?? NodeType.STANDARD;
+    this.cpuArch = props.cpuArch ?? CpuArch.X86_64;
     this.kubernetesVersion = props.kubernetesVersion ?? LATEST_KUBERNETES_VERSION;
 
     // set the SSM parameter name
     this.amiParameterName = `/aws/service/eks/optimized-ami/${this.kubernetesVersion}/`
-      + ( this.nodeType === NodeType.STANDARD ? 'amazon-linux-2/' : '' )
+      + ( this.nodeType === NodeType.STANDARD ? this.cpuArch === CpuArch.X86_64 ?
+        'amazon-linux-2/' : 'amazon-linux-2-arm64/' :'' )
       + ( this.nodeType === NodeType.GPU ? 'amazon-linux-2-gpu/' : '' )
       + (this.nodeType === NodeType.INFERENTIA ? 'amazon-linux-2-gpu/' : '')
       + 'recommended/image_id';
@@ -1739,6 +1750,21 @@ export enum NodeType {
   INFERENTIA = 'INFERENTIA',
 }
 
+/**
+ * CPU architecture
+ */
+export enum CpuArch {
+  /**
+   * arm64 CPU type
+   */
+  ARM_64 = 'arm64',
+
+  /**
+   * x86_64 CPU type
+   */
+  X86_64 = 'x86_64',
+}
+
 /**
  * The type of compute resources to use for CoreDNS.
  */
@@ -1782,12 +1808,15 @@ export enum MachineImageType {
   BOTTLEROCKET
 }
 
-const GPU_INSTANCETYPES = ['p2', 'p3', 'g4'];
-const INFERENTIA_INSTANCETYPES = ['inf1'];
-
 function nodeTypeForInstanceType(instanceType: ec2.InstanceType) {
-  return GPU_INSTANCETYPES.includes(instanceType.toString().substring(0, 2)) ? NodeType.GPU :
-    INFERENTIA_INSTANCETYPES.includes(instanceType.toString().substring(0, 4)) ? NodeType.INFERENTIA :
+  return INSTANCE_TYPES.gpu.includes(instanceType.toString().substring(0, 2)) ? NodeType.GPU :
+    INSTANCE_TYPES.inferentia.includes(instanceType.toString().substring(0, 4)) ? NodeType.INFERENTIA :
       NodeType.STANDARD;
 }
 
+function cpuArchForInstanceType(instanceType: ec2.InstanceType) {
+  return INSTANCE_TYPES.graviton2.includes(instanceType.toString().substring(0, 3)) ? CpuArch.ARM_64 :
+    INSTANCE_TYPES.graviton.includes(instanceType.toString().substring(0, 2)) ? CpuArch.ARM_64 :
+      CpuArch.X86_64;
+}
+

packages/@aws-cdk/aws-eks/lib/instance-types.ts

@@ -0,0 +1,6 @@
+export const INSTANCE_TYPES = {
+  gpu: ['p2', 'p3', 'g2', 'g3', 'g4'],
+  inferentia: ['inf1'],
+  graviton: ['a1'],
+  graviton2: ['c6g', 'm6g', 'r6g'],
+};

packages/@aws-cdk/aws-eks/lib/managed-nodegroup.ts

@@ -3,6 +3,7 @@ import { IRole, ManagedPolicy, Role, ServicePrincipal } from '@aws-cdk/aws-iam';
 import { Construct, IResource, Resource } from '@aws-cdk/core';
 import { Cluster, ICluster } from './cluster';
 import { CfnNodegroup } from './eks.generated';
+import { INSTANCE_TYPES } from './instance-types';
 
 /**
  * NodeGroup interface
@@ -22,13 +23,17 @@ export interface INodegroup extends IResource {
  */
 export enum NodegroupAmiType {
   /**
-   * Amazon Linux 2
+   * Amazon Linux 2 (x86-64)
    */
   AL2_X86_64 = 'AL2_x86_64',
   /**
    * Amazon Linux 2 with GPU support
    */
   AL2_X86_64_GPU = 'AL2_x86_64_GPU',
+  /**
+   * Amazon Linux 2 (ARM-64)
+   */
+  AL2_ARM_64 = 'AL2_ARM_64'
 }
 
 /**
@@ -73,7 +78,7 @@ export interface NodegroupOptions {
   /**
    * The AMI type for your node group.
    *
-   * @default AL2_x86_64
+   * @default - auto-determined from the instanceType property.
    */
   readonly amiType?: NodegroupAmiType;
   /**
@@ -243,7 +248,8 @@ export class Nodegroup extends Resource implements INodegroup {
       nodegroupName: props.nodegroupName,
       nodeRole: this.role.roleArn,
       subnets: this.cluster.vpc.selectSubnets(props.subnets).subnetIds,
-      amiType: props.amiType,
+      amiType: props.amiType ?? (props.instanceType ? getAmiTypeForInstanceType(props.instanceType).toString() :
+        undefined),
       diskSize: props.diskSize,
       forceUpdateEnabled: props.forceUpdate ?? true,
       instanceTypes: props.instanceType ? [props.instanceType.toString()] : undefined,
@@ -282,5 +288,13 @@ export class Nodegroup extends Resource implements INodegroup {
     });
     this.nodegroupName = this.getResourceNameAttribute(resource.ref);
   }
+}
 
+function getAmiTypeForInstanceType(instanceType: InstanceType) {
+  return INSTANCE_TYPES.graviton2.includes(instanceType.toString().substring(0, 3)) ? NodegroupAmiType.AL2_ARM_64 :
+    INSTANCE_TYPES.graviton.includes(instanceType.toString().substring(0, 2)) ? NodegroupAmiType.AL2_ARM_64 :
+      INSTANCE_TYPES.gpu.includes(instanceType.toString().substring(0, 2)) ? NodegroupAmiType.AL2_X86_64_GPU :
+        INSTANCE_TYPES.inferentia.includes(instanceType.toString().substring(0, 4)) ? NodegroupAmiType.AL2_X86_64_GPU :
+          NodegroupAmiType.AL2_X86_64;
 }
+

packages/@aws-cdk/aws-eks/test/integ.eks-cluster-private-endpoint.expected.json

@@ -1050,6 +1050,7 @@
             "Ref": "VpcPrivateSubnet3SubnetF258B56E"
           }
         ],
+        "AmiType": "AL2_x86_64",
         "ForceUpdateEnabled": true,
         "InstanceTypes": [
           "m5.large"