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Cheatsheet: Kubernetes (K8s)


Namespaces:

- Namespaces are used as a means to separate k8s resources

Create Namespace

kubectl create ns <--namespace-->

Get all namespaces

kubectl get namespaces

Pod:

- Pod allows you to run the application in a container
- Usually the config for pods are defined in YAML, but you can create a quick pod using "run" command.

kubectl run <--pod-name--> --image=nginx:2.3.5 --restart=Never --port=80 --namespace=<--namespace-->

View pods details

kubectl get pod -n <--namespace-->

Describe pod:
- This will provide much deeper insight into the pod

kubectl describe pod -n <--namespace-->

Modify pod

*Replace xyzPod with your pod name below
 
kubectl set image pod xyzPod xyzPod=nginx --namespace=<--namespace-->

Check Pod status:

kubectl get pod -n <--namespace-->

Shell into container:

kubectl exec <--pod-name--> -it --namespace=<--namespace--> -- /bin/sh

- exit from shell

#exit

Access Pod logs:

kubectl logs <--pod-name--> -n <--namespace-->

Delete K8s Resources:

- Pod:
kubectl delete pod <--pod-name--> --namespace=<--namespace-->

- namespace:
kubectl delete namespace <--namespace-->

Force delete - K8s tries to gracefully delete the resources, if you want to speed-up the process and want to force delete the resources. Use the following command-line option.

     --grace-period=0 --force


Happy coding ðŸ‘¨‍💻
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