Validating the Kubernetes cluster

3 min readFeb 11, 2022

We will validate the K8s cluster configured using kubeadm in the previous article and we will also deploy the sample deployment and will ensure everything is working as it should be.

Validating CMD Tools

Ensure kubeadm and kubectl version is as per your cluster setup.

$ kubeadm version

$ kubeadm version --short

2. Validating Cluster Nodes

Ensure all nodes including Master and Worker nodes are Ready state.

$ kubectl get nodes 
$ kubectl get nodes -o wide

3. Validating Kubernetes Components

Ensure all K8s Master node components are in Running state.

$ kubectl get pods -n kube-system

$ kubectl get pods -n kube-system -o wide

4. Validating Services: Docker & Kubelet

Ensure Docker and Kubelet Services are “Active(Running) and Enabled on all nodes.

$ systemctl status docker

$ systemctl status kubelet

5. Deploying the Nginx application.

a) Let's create a deployment on the master node named “Nginx-deploy” using YAML.

$ vi nginx-deploy.yaml

Deployment YAML file should like below

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  labels:
    app: nginx-app
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx-app
  template:
    metadata:
      labels:
        app: nginx-app
    spec:
      containers:
      - name: nginx-container
        image: nginx:latest
        ports:
        - containerPort: 80

b) Let's create a pod using kubectl command

$ kubectl apply -f nginx-deploy.yaml

c) Let's check Pod status

$ kubectl get pods
$ kubectl get pods -o wide

d) Expose the Nginx deployment using Kubernetes NodePort (32001) service

$ vi nginx-service.yaml

e) Service YAML file

apiVersion: v1
kind: Service
metadata:
  name: nginx-app
spec:
  selector: 
    app: nginx-app
  type: NodePort  
  ports:
    - port: 80
      targetPort: 80
      nodePort: 32001

f) Create a Service using the kubectl command