Managed Node Group Cluster Provider

The MngClusterProvider allows you to provision an EKS cluster which leverages EKS managed node groups(MNGs) for compute capacity. MNGs automate the provisioning and lifecycle management of nodes (Amazon EC2 instances) for Amazon EKS Kubernetes clusters.

Usage

const props: MngClusterProviderProps = {
    minSize: 1,
    maxSize: 10,
    desiredSize: 4,
    version: "auto"
    instanceTypes: [new InstanceType('m5.large')],
    amiType: NodegroupAmiType.AL2_X86_64,
    nodeGroupCapacityType: CapacityType.ON_DEMAND,
    version: KubernetesVersion.V1_29,
    amiReleaseVersion: "1.20.4-20210519" // this will upgrade kubelet to 1.20.4
}
const clusterProvider = new blueprints.MngClusterProvider(props);
new blueprints.EksBlueprint(scope, { id: 'blueprint', [], [], clusterProvider });

Configuration

The MngClusterProvider supports the following configuration options.

Prop	Description
name	The name for the cluster. @Deprecated
clusterName	Cluster name
version	Kubernetes version for the control plane. Required in cluster props or blueprint props.
minSize	Min cluster size, must be positive integer greater than 0 (default 1).
maxSize	Max cluster size, must be greater than minSize (default 3).
desiredSize	Desired cluster size, must be greater or equal to minSize (default min-size).
instanceTypes	Type of instance for the EKS cluster, must be a valid instance type, i.e. t3.medium (default "m5.large")
amiType	The AMI type for the managed node group.
amiReleaseVersion	The AMI Kubernetes release version for the node group.
customAmi	The custom AMI and the userData for the node group, amiType and amiReleaseVersion will be ignored if this is set.
nodeGroupCapacityType	The capacity type for the node group (on demand or spot).
vpcSubnets	The subnets for the cluster.
privateCluster	If true Kubernetes API server is private.
tags	Tags to propagate to Cluster.
nodeGroupTags	Tags to propagate to Node Group.

There should be public and private subnets for EKS cluster to work. For more information see Cluster VPC Considerations.

Configuration can also be supplied via context variables (specify in cdk.json, cdk.context.json, ~/.cdk.json or pass with -c command line option):

• eks.default.min-size
• eks.default.max-size
• eks.default.desired-size
• eks.default.instance-type
• eks.default.private-cluster

Configuration of the EC2 parameters through context parameters makes sense if you would like to apply default configuration to multiple clusters without the need to explicitly pass MngClusterProviderProps to each cluster blueprint.

You can find more details on the supported configuration options in the API documentation for the MngClusterProviderProps.

Upgrading Worker Nodes

Upgrading Kubernetes versions via cluster configuration at present won't impact the kubelet version running on the worker nodes. To perform an in-place upgrade of the cluster, you must also update the amiReleaseVersion property. The following demonstrates how to do so.

const props: MngClusterProviderProps = {
    version: KubernetesVersion.V1_29,
    amiReleaseVersion: "1.25.7-20230509" // this will upgrade kubelet to 1.25
}

Note: consult the official EKS documentation for information ion the AMI release version that matches Kubernetes versions.

Creating Clusters with Spot Capacity Type

To create clusters which leverage Spot capacity, set the nodeGroupCapacityType value to CapacityType.SPOT

const props: MngClusterProviderProps = {
    nodeGroupCapacityType: CapacityType.SPOT,
    version: KubernetesVersion.V1_29,
    instanceTypes: [new InstanceType('t3.large'), new InstanceType('m5.large')],
    amiReleaseVersion: "1.25.7-20230509" // this will upgrade kubelet to 1.25
}

Note that two attributes in this configuration are relevant for Spot: nodeGroupCapacityType and instaceTypes. The latter indicates the types of instances which could be leveraged for Spot capacity and it makes sense to have a number of instance types to maximize availability.

Creating Clusters with custom AMI for the node group

To create clusters using custom AMI for the worker nodes, set the customAmi to your custom image and provide your userData for node bootstrapping.

const userData = UserData.forLinux();
userData.addCommands(`/etc/eks/bootstrap.sh ${cluster.clusterName}`);

const props: MngClusterProviderProps = {
    nodeGroupCapacityType: CapacityType.ON_DEMAND,
    version: KubernetesVersion.V1_29,
    instanceTypes: [new InstanceType('t3.large')],
    customAmi: {
        machineImage: MachineImage.genericLinux({'us-east-1': 'ami-0be34337b485b2609'}),
        userData: userData,
    },
}