Kubernetes Commands and Syntax for CKA Exam

General Management

kubectl get [resource]: List resources. For example, kubectl get pods.
kubectl describe [resource] [name]: Show detailed information about a resource. For example, kubectl describe pod my-pod.

Creating and Managing Resources

kubectl create -f [file.yaml]: Create a resource from a YAML file.
kubectl apply -f [file.yaml]: Apply a configuration to a resource from a YAML file.
kubectl delete [resource] [name]: Delete a resource. For example, kubectl delete pod my-pod.
kubectl edit [resource] [name]: Edit the configuration of a resource.

Namespaces

kubectl get namespaces: List all namespaces.
kubectl create namespace [name]: Create a new namespace.

Pods

kubectl run [name] --image=[image]: Run a pod with a specific image.
kubectl exec -it [pod-name] -- [command]: Execute a command in a running pod.

Deployments and Replicas

kubectl scale deployment [deployment-name] --replicas=[number]: Scale a deployment to the specified number of replicas.
kubectl rollout status deployment/[deployment-name]: Get the rollout status of a deployment.
kubectl rollout undo deployment/[deployment-name]: Rollback to the previous deployment.

Services

kubectl expose deployment [deployment-name] --type=[type] --port=[port]: Expose a deployment as a new Kubernetes service.

Logs and Debugging

kubectl logs [pod-name]: Fetch the logs of a pod.
kubectl logs -f [pod-name]: Stream the logs of a pod.

Node Management

kubectl get nodes: List all nodes in the cluster.
kubectl cordon [node-name]: Mark node as unschedulable.
kubectl drain [node-name]: Drain node in preparation for maintenance.

Resource Inspection

kubectl top pod: Display metrics for pods.
kubectl top node: Display metrics for nodes.

Configuration

kubectl config view: View Kubernetes configuration.
kubectl config use-context [context-name]: Switch to a different cluster context.

kubectl Cheat Sheet

Kubernetes has an official kubectl cheat sheet which is an invaluable resource: https://kubernetes.io/docs/reference/kubectl/cheatsheet/

Tips for Using kubectl Commands

Understand Contexts: Know how to switch contexts if you’re working with multiple clusters.
Use YAML Files for Complex Configurations: While imperative commands are useful, declarative configurations using YAML are more consistent and repeatable.
Explore kubectl Autocomplete: It can significantly speed up command entry.
Remember Selectors: They are powerful for filtering results, especially with get commands.

This cheat sheet covers the fundamental concepts and commands that are essential for the CKA exam and day-to-day Kubernetes administration. Remember, hands-on practice and familiarity with the official Kubernetes documentation are key to success in the CKA exam.