How to configure Metrics Server on kubeadm provisioned Kubernetes cluster?
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Metrics server is the kubernetes cluster-wide aggregator of resource usage data. Let me take you the steps for configuration on bare metal. The official documentation has some missing links. Kubernetes installed through kubeadm doesn’t have the metrics server installed by default. Also it does not guarantee secure communication as the certificates generated by kubeadm are self-signed. Below is the step-by-step guide.
Clone the repos using this link.
Modify the metrics-server-deployment as below. (Modifications highlighted):
spec:
serviceAccountName: metrics-server
volumes:
# mount in tmp so we can safely use from-scratch images and/or read-only containers
- name: tmp-dir
emptyDir: {}
hostAliases:
- hostnames:
- k8smaster
ip: 10.0.0.45
- hostnames:
- k8sworker1
ip: 10.0.0.46 #Mention all worker node’s hostname and ip.
containers:
- name: metrics-server
image: k8s.gcr.io/metrics-server-amd64:v0.3.1
command:
- /metrics-server
-— kubelet-preferred-address-types=InternalDNS,InternalIP,ExternalDNS,ExternalIP,Hostname
- — kubelet-insecure-tls
Now deploy the server using below command:
# Kubernetes > 1.8
$ kubectl create -f deploy/1.8+/
Wait for few minutes for metric server and API to distribute and fetch relevant information.
Now verify your deployment using:
Kubectl top nodes
Kubectl top pods
