Managing a Kubernetes cluster involves various tasks, such as deploying applications, scaling resources, checking the cluster’s health, and more. Below are some examples of common operations to manage a Kubernetes cluster using the kubectl command-line tool:

Deploying an Application: To deploy an application on the Kubernetes cluster, you’ll need a YAML manifest file describing the deployment. Here’s an example YAML file for a basic Nginx web server deployment:nginx-deployment.yaml:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80

To create the deployment, use the kubectl apply command:

kubectl apply -f nginx-deployment.yaml

Scaling a Deployment: You can scale the number of replicas in a deployment using the kubectl scale command:

# Scale the 'nginx-deployment' to 5 replicas
kubectl scale deployment nginx-deployment --replicas=5

Checking Cluster Nodes: To see the list of nodes in the cluster, use the kubectl get nodes command:

kubectl get nodes

Checking Cluster Pods: To list all the pods running in the cluster, use the kubectl get pods command:

kubectl get pods --all-namespaces

Viewing Pod Logs: To view the logs of a specific pod, use the kubectl logs command:

# Replace 'pod-name' and 'namespace' with the actual pod and namespace names
kubectl logs pod-name -n namespace

Updating a Deployment: To update the image of a deployment, modify the YAML file with the new image tag and then use kubectl apply again:

# Edit the nginx-deployment.yaml file with the new image tag
vim nginx-deployment.yaml

# Apply the changes to the deployment
kubectl apply -f nginx-deployment.yaml

Deleting Resources: To delete resources like a deployment, service, or pod, use the kubectl delete command:

# Delete a deployment
kubectl delete deployment nginx-deployment

# Delete a service
kubectl delete service my-service

# Delete a pod
kubectl delete pod pod-name

These are just a few examples of common operations to manage a Kubernetes cluster using kubectl. There are many more features and functionalities available to manage and monitor Kubernetes clusters. Always refer to the official Kubernetes documentation and other resources for more in-depth knowledge and advanced management tasks.