View resource usage with the KubernetesMetrics Server - Amazon EKS

View resource usage with the KubernetesMetrics Server

The Kubernetes Metrics Server is an aggregator of resource usage data in your cluster, and it isn’t deployed by default in Amazon EKS clusters. For more information, see Kubernetes Metrics Server on GitHub. The Metrics Server is commonly used by other Kubernetes add ons, such as the Scale pod deployments with Horizontal Pod Autoscaler or the Kubernetes Dashboard. For more information, see Resource metrics pipeline in the Kubernetes documentation. This topic explains how to deploy the Kubernetes Metrics Server on your Amazon EKS cluster.

Important

The metrics are meant for point-in-time analysis and aren’t an accurate source for historical analysis. They can’t be used as a monitoring solution or for other non-auto scaling purposes. For information about monitoring tools, see Monitor your cluster performance and view logs.

  1. Deploy the Metrics Server with the following command:

    kubectl apply -f https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml

    If you are using Fargate, you will need to change this file. In the default configuration, the metrics server uses port 10250. This port is reserved on Fargate. Replace references to port 10250 in components.yaml with another port, such as 10251.

  2. Verify that the metrics-server deployment is running the desired number of Pods with the following command.

    kubectl get deployment metrics-server -n kube-system

    An example output is as follows.

    NAME             READY   UP-TO-DATE   AVAILABLE   AGE
metrics-server   1/1     1            1           6m

  3. Test the metrics server is working by displaying resource (CPU/memory) usage of nodes.

    kubectl top nodes

  4. If you receive the error message Error from server (Forbidden), you need to update your Kubernetes RBAC configuration. Your Kubernetes RBAC identity needs sufficent permissions to read cluster metrics. Review thehttps://github.com/kubernetes-sigs/metrics-server/blob/e285375a49e3bf77ddd78c08a05aaa44f2249ebd/manifests/base/rbac.yaml#L5C9-L5C41[minimum required Kubernetes API permissions for reading metrics] on GitHub. Learn how togrant AWS IAM Identities such as Roles access to Kubernetes APIs.