Essential Kubernetes Commands with Simple Explanations

 Kubernetes, or K8s, is a leading container orchestration platform that simplifies the deployment and management of applications. Knowing the right commands is key to navigating Kubernetes effectively. Here’s a guide to important Kubernetes commands explained in simple terms.

1. kubectl version

Command:

kubectl version --short

This command shows the versions of both the client and server components of Kubernetes. It helps ensure your kubectl tool is compatible with the cluster.

2. kubectl get

Command:

kubectl get pods
kubectl get services
kubectl get nodes

• kubectl get pods lists all pods in the current namespace.
• kubectl get services displays all services, such as load balancers and cluster IPs.
• kubectl get nodes shows all nodes in the cluster.

You can use the -A or --all-namespaces flag to view resources across all namespaces.

3. kubectl describe

Command:

kubectl describe pod <pod-name>
kubectl describe service <service-name>

This command provides detailed information about a specific resource. For instance, kubectl describe pod <pod-name> displays details like events, resource limits, and configurations for the specified pod.

4. kubectl create

Command:

kubectl create deployment nginx --image=nginx

Creates a deployment with a specified name and container image. For example, the above command deploys an NGINX server.

5. kubectl apply

Command:

kubectl apply -f <manifest.yaml>

Applies a configuration file (YAML or JSON) to create or update resources declaratively.

6. kubectl delete

Command:

kubectl delete pod <pod-name>
kubectl delete -f <manifest.yaml>

Deletes specified resources. You can remove individual resources or those defined in a manifest file.

7. kubectl logs

Command:

kubectl logs <pod-name>
kubectl logs <pod-name> -c <container-name>

Fetches logs from a pod. If the pod has multiple containers, you can specify one using the -c flag.

8. kubectl exec

Command:

kubectl exec -it <pod-name> -- /bin/bash

Opens an interactive shell session in a running pod. This is especially useful for debugging or troubleshooting applications.

9. kubectl port-forward

Command:

kubectl port-forward pod/<pod-name> 8080:80

Forwards a local port to a port on a pod, allowing you to access services running within the pod locally.

10. kubectl scale

Command:

kubectl scale deployment <deployment-name> --replicas=3

Scales a deployment to the desired number of replicas. This adjusts the number of pods running for an application.

11. kubectl rollout

Command:

kubectl rollout status deployment <deployment-name>
kubectl rollout undo deployment <deployment-name>

• rollout status monitors the status of a deployment rollout.
• rollout undo rolls back to a previous version of a deployment.

12. kubectl top

Command:

kubectl top pod
kubectl top node

Displays resource usage, such as CPU and memory, for pods or nodes. Make sure the Metrics Server is installed for this command.

13. kubectl config

Command:

kubectl config get-contexts
kubectl config use-context <context-name>

Manages Kubernetes contexts, enabling you to switch between clusters or namespaces.

14. kubectl expose

Command:

kubectl expose deployment <deployment-name> --type=NodePort --port=80

Exposes a deployment as a service, making it accessible externally or internally based on the type specified.

15. kubectl get events

Command:

kubectl get events

Lists cluster events, including warnings and errors. This is useful for monitoring and troubleshooting.

Kubernetes commands can simplify complex tasks, making cluster management more efficient. By mastering these essential commands, you can navigate Kubernetes with confidence and tackle day-to-day tasks effectively. Start practicing today and enhance your Kubernetes skills!