Cluster Autoscaler

Install/upgrade/uninstall Cluster Autoscaler

If you have not already done so, make sure your EKS Anywhere cluster meets the package prerequisites.

Refer to the troubleshooting guide in the event of a problem.

Enable Cluster Autoscaling

  1. Ensure you have configured at least one worker node group in your cluster specification to enable autoscaling as outlined in Autoscaling configuration. Cluster Autoscaler only works on node groups with an autoscalingConfiguration set:

    kind: Cluster
      name: <cluster-name>
        - autoscalingConfiguration:
            minCount: 1
            maxCount: 5
            kind: VSphereMachineConfig
            name: <worker-machine-config-name>
          count: 1
          name: md-0
  2. Generate the package configuration.

    eksctl anywhere generate package cluster-autoscaler --cluster <cluster-name> > cluster-autoscaler.yaml
  3. Add the desired configuration to cluster-autoscaler.yaml. See configuration options for all configuration options and their default values. See below for an example package file configuring a Cluster Autoscaler package.

    kind: Package
      name: cluster-autoscaler-<cluster-name>
      namespace: eksa-packages-<cluster-name>
      packageName: cluster-autoscaler
      targetNamespace: default
      config: |-
          cloudProvider: "clusterapi"
            clusterName: "<cluster-name>"      
  4. Install Cluster Autoscaler

    eksctl anywhere create packages -f cluster-autoscaler.yaml
  5. Validate the installation

    eksctl anywhere get packages --cluster <cluster-name>
    NAMESPACE                  NAME                          PACKAGE              AGE   STATE       CURRENTVERSION                                               TARGETVERSION                                                         DETAIL
    eksa-packages-mgmt-v-vmc   cluster-autoscaler            cluster-autoscaler   18h   installed   9.21.0-1.21-147e2a701f6ab625452fe311d5c94a167270f365         9.21.0-1.21-147e2a701f6ab625452fe311d5c94a167270f365 (latest)

    To verify that autoscaling works, apply the deployment below. You must continue scaling pods until the deployment has pods in a pending state. This is when Cluster Autoscaler will begin to autoscale your machine deployment. This process may take a few minutes.

    kubectl apply -f
    kubectl scale deployment hpa-busybox-test --replicas 100


To update package configuration, update the cluster-autoscaler.yaml file and run the following command:

eksctl anywhere apply package -f cluster-autoscaler.yaml

Update Worker Node Group Autoscaling Configuration

It is possible to change the autoscaling configuration of a worker node group by updating the autoscalingConfiguration in your cluster specification and running a cluster upgrade.


The Cluster Autoscaler can be upgraded by PackageController’s activeBundle field to a newer version. The curated packages bundle contains the SHAs of the images and helm charts associated with a particular package. When a new version is activated, the Package Controller will reconcile all active packages to their newest versions as defined in the bundle. The Curated Packages Controller automatically polls the bundle repository for new bundle resources. The curated packages controller automatically polls for the latest bundle, but requires the activeBundle field on the PackageController resource to be updated before a new bundle will take effect and upgrade the resources.


To uninstall Cluster Autoscaler, delete the package

eksctl anywhere delete package --cluster <cluster-name> cluster-autoscaler