1. Define a yml file: nginx.pod.yml:
apiVersion: v1 kind: Pod metadata: name: my-nginx labels: app: nginx rel: stable spec: containers: - name: my-nginx image: nginx:alpine ports: - containerPort: 80 resources:
It creates my-nginx pod.
2. We the yml file with kubectl:
kubectl create -f nginx.pod.yml --save-config
We use '--save-config' option.
If we run:
kubectl get pods my-nginx -o yaml
It outpus the configurations for my-nginx pod:
... metadata: annotations: kubectl.kubernetes.io/last-applied-configuration: | {"apiVersion":"v1","kind":"Pod","metadata":{"annotations":{},"labels":{"app":"nginx","rel":"stable"},"name":"my-nginx","namespace":"default"},"spec":{"containers":[{"image":"nginx:alpine","name":"my-nginx","ports":[{"containerPort":80}],"resources":null}]}} ...
It save the the configuration for this pod, so later if I udpated the yml file, it will diff the changes, and only apply the changes to the pod.
3. apply vs create:
kubectl apply -f nginx.pod.yml // pod/my-nginx configured
The nice thing of 'apply' is: if the pod is not there, it will create the resource, if the pod is there, then it will update the resource.
4. Get into the pod:
kubectl exec my-nginx -it sh
Quite you can type:
exit
5. Delete the pod:
This time actually we only have pod, without develoyment, so we can delete the pod by:
kubectl delete pod my-nginx
kubectl delete -f nginx.pod.yml