dhi.io/karpenter-chart
Karpenter
Open-source Kubernetes node autoscaler built for flexibility, performance, and simplicity
Installing the chart
Prerequisites
- Kubernetes 1.23+
- Helm 3.0+
- AWS account with appropriate IAM permissions (IRSA or EKS Pod Identities)
Installation steps
All examples in this guide use the public chart and images. If you've mirrored the repository for your own use (for example, to your Docker Hub namespace), update your commands to reference the mirrored chart instead of the public one.
For example:
- Public chart:
dhi.io/<repository>:<tag> - Mirrored chart:
<your-namespace>/dhi-<repository>:<tag>
For more details about customizing the chart to reference other images, see the documentation.
Step 1: Optional. Mirror the Helm chart and/or its images to your own registry
To optionally mirror a chart to your own third-party registry, you can follow the instructions in How to mirror an image for either the chart, the image, or both.
The same regctl tool that is used for mirroring container images can also be used for mirroring Helm charts, as Helm
charts are OCI artifacts.
For example:
regctl image copy \
"${SRC_CHART_REPO}:${TAG}" \
"${DEST_REG}/${DEST_CHART_REPO}:${TAG}" \
--referrers \
--referrers-src "${SRC_ATT_REPO}" \
--referrers-tgt "${DEST_REG}/${DEST_CHART_REPO}" \
--force-recursive
Step 2: Create a Kubernetes secret for pulling images
The Docker Hardened Images that the chart uses require authentication. To allow your Kubernetes cluster to pull those images, you need to create a Kubernetes secret with your Docker Hub credentials or with the credentials for your own registry.
Follow the authentication instructions for DHI in Kubernetes.
For example:
kubectl create secret docker-registry helm-pull-secret \
--docker-server=dhi.io \
--docker-username=<Docker username> \
--docker-password=<Docker token> \
--docker-email=<Docker email>
Step 3: Install the Helm chart
To install the chart, use helm install. Make sure you use helm login to log in before running helm install.
Optionally, you can also use the --dry-run flag to test the installation without actually installing anything.
Note: The chart's default imagePullSecrets value is an empty array []. You need to override it with your pull
secret name.
helm install my-karpenter oci://dhi.io/karpenter-chart --version <version> \
--set "imagePullSecrets[0].name=helm-pull-secret" \
--set "settings.clusterName=<your-cluster-name>" \
--set "settings.interruptionQueue=<your-interruption-queue>" \
--namespace kube-system \
--set controller.resources.requests.cpu=1 \
--set controller.resources.requests.memory=1Gi \
--set controller.resources.limits.cpu=1 \
--set controller.resources.limits.memory=1Gi \
--set "controller.env[0].name=AWS_REGION" \
--set "controller.env[0].value=us-east-1" \
--set "serviceAccount.name=karpenter" \
--set replicas=1
Replace <version> accordingly. If the chart is in your own registry or repository, replace dhi.io with your own
registry and namespace. Replace helm-pull-secret with the name of the image pull secret you created earlier.
Step 4: Verify the installation
Check that the Karpenter controller is running:
kubectl get all -n kube-system
NAME READY STATUS RESTARTS AGE
pod/aws-node-kf5bd 2/2 Running 0 3d13h
pod/coredns-6d58b7d47c-2c7s8 1/1 Running 0 3d13h
pod/coredns-6d58b7d47c-mg4k5 1/1 Running 0 3d13h
pod/eks-pod-identity-agent-zdnlt 1/1 Running 0 3d13h
pod/karpenter-karpenter-chart-696c6d566d-pjxd8 1/1 Running 0 3d1h
pod/kube-proxy-4t7jr 1/1 Running 0 3d13h
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
service/eks-extension-metrics-api ClusterIP 172.20.63.115 <none> 443/TCP 3d23h
service/karpenter-karpenter-chart ClusterIP 172.20.169.56 <none> 8080/TCP 3d1h
service/kube-dns ClusterIP 172.20.0.10 <none> 53/UDP,53/TCP,9153/TCP 3d23h
NAME DESIRED CURRENT READY UP-TO-DATE AVAILABLE NODE SELECTOR AGE
daemonset.apps/aws-node 1 1 1 1 1 <none> 3d23h
daemonset.apps/eks-pod-identity-agent 1 1 1 1 1 <none> 3d23h
daemonset.apps/kube-proxy 1 1 1 1 1 <none> 3d23h
NAME READY UP-TO-DATE AVAILABLE AGE
deployment.apps/coredns 2/2 2 2 3d23h
deployment.apps/karpenter-karpenter-chart 1/1 1 1 3d1h
NAME DESIRED CURRENT READY AGE
replicaset.apps/coredns-6d58b7d47c 2 2 2 3d23h
replicaset.apps/karpenter-karpenter-chart-696c6d566d 1 1 1 3d1h
You should see the Karpenter controller pod in a Running state.
Step 5: Install Karpenter CRDs
A simple way to deploy the necessary IAM roles and permissions is through the Karpenter Terraform module:
Before Karpenter can provision nodes, you need to:
Set up IAM roles and policies as described in the Karpenter documentation.
Create an EC2NodeClass to define the AWS-specific configuration for nodes:
apiVersion: karpenter.k8s.aws/v1beta1
kind: EC2NodeClass
metadata:
name: default
namespace: kube-system
spec:
amiFamily: AL2
role: "KarpenterNodeRole-<your-cluster-name>"
subnetSelectorTerms:
- tags:
karpenter.sh/discovery: "<your-cluster-name>"
securityGroupSelectorTerms:
- tags:
karpenter.sh/discovery: "<your-cluster-name>"
- Create a NodePool to define the provisioning constraints:
apiVersion: karpenter.sh/v1
kind: NodePool
metadata:
name: default
namespace: kube-system
spec:
template:
metadata:
labels:
intent: demo
spec:
nodeClassRef:
group: karpenter.k8s.aws
kind: EC2NodeClass
name: default
requirements:
- key: kubernetes.io/os
operator: In
values: ["linux"]
- key: kubernetes.io/arch
operator: In
values: ["amd64"]
- key: karpenter.sh/capacity-type
operator: In
values: ["on-demand"]
- key: karpenter.k8s.aws/instance-category
operator: In
values: ["t", "m", "c"]
- key: karpenter.k8s.aws/instance-generation
operator: Gt
values: ["2"]
disruption:
consolidationPolicy: WhenEmptyOrUnderutilized
consolidateAfter: 30s
limits:
cpu: "16"
- Make a test deployment to trigger Karpenter Node allocation
apiVersion: apps/v1
kind: Deployment
metadata:
name: inflate
spec:
replicas: 3
selector:
matchLabels:
app: inflate
template:
metadata:
labels:
app: inflate
spec:
terminationGracePeriodSeconds: 0
containers:
- name: inflate
image: public.ecr.aws/eks-distro/kubernetes/pause:3.9
resources:
requests:
cpu: "1"
For complete setup instructions, including IAM configuration and advanced NodePool settings, refer to the official Karpenter documentation at https://karpenter.sh/docs/.