Preparing effectively for the Certified Kubernetes Application Developer (CKAD) certification involves a combination of hands-on exercises and focused demo rehearsals. This certification assesses your ability to design, deploy, and manage applications on Kubernetes clusters efficiently.
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kubectl run nginx --image nginx kubectl get pods -o=jsonpath='{range .items[*]}{range .status.containerStatuses[?(@.state.running)]}{"\tContainer Name: "}{.name}{"\tRunning: "}{.state.running}{"\tReadyStatus: "}{.ready}{"\n"}{end}{end}'Create a new service exposing the pod as a nodePort, which presents a working webserver configured in the previousstep
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kubectl create service nodeport svc --tcp=5678:80 --dry-run -o yaml > svc.yamlvi svc.yamlapiVersion: v1
kind: Service
metadata:
creationTimestamp: null
labels:
app: svc
name: svc
spec:
ports:
- name: 5678-80
port: 5678
protocol: TCP
targetPort: 80
selector:
run: nginx # Add run: nginx selector
type: NodePort
status:
loadBalancer: {}>ctr:x!kubectl apply -f svc.yamlkubectl get svc svc -o wideNAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR
svc NodePort 10.110.220.208 <none> 5678:31030/TCP 20m run=nginxcurl 10.110.220.208:5678 // from the same vmcurl 10.110.220.208:31030 // from the your local machine or navigatorUpdate the pod to run thenginx:1.11-alpineimage and re-verify you can view the webserver via a nodePort
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kubectl edit pod nginx apiVersion: v1
kind: Pod
metadata:
creationTimestamp: "2024-05-07T20:21:50Z"
labels:
run: nginx
name: nginx
namespace: default
resourceVersion: "141816"
uid: a7e2720e-3a8e-46bc-af6f-93e1d1b55a88
spec:
containers:
- image: nginx:1.11-alpine # change here
imagePullPolicy: Always
>ctr:x!kubectl get pod nginxNAME READY STATUS RESTARTS AGE
nginx 1/1 Running 1 (5m53s ago) 40mkubectl describe pod nginxName: nginx
Namespace: default
Priority: 0
Service Account: default
Node: ip-172-31-28-164/172.31.28.164
Start Time: Tue, 07 May 2024 20:21:50 +0000
Labels: run=nginx
Annotations: <none>
Status: Running
IP: 10.0.2.145
IPs:
IP: 10.0.2.145
Containers:
nginx:
Container ID: containerd://f9d93fb6dbd4d69d7e9de30747591d55feb95b31cd6da55ab8fcd1b8a2c6047b
Image: nginx:1.11-alpine // => should be the new nginx version
curl 10.110.220.208:5678 // from the same vmcurl 10.110.220.208:31030 // from the your local machine or navigator<!DOCTYPE html>
<html>
<head>
<title>Welcome to nginx!</title>
<style>
body {
width: 35em;
margin: 0 auto;
font-family: Tahoma, Verdana, Arial, sans-serif;
}
</style>
</head>
<body>
<h1>Welcome to nginx!</h1>
<p>If you see this page, the nginx web server is successfully installed and
working. Further configuration is required.</p>
<p>For online documentation and support please refer to
<a href="http://nginx.org/">nginx.org</a>.<br/>
Commercial support is available at
<a href="http://nginx.com/">nginx.com</a>.</p>
<p><em>Thank you for using nginx.</em></p>
</body>
</html>
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vim job.yaml kubectapiVersion: batch/v1
kind: Job
metadata:
name: my-job
spec:
template:
spec:
containers:
- name: my-container
image: busybox
command: ["sleep", "5"]
restartPolicy: Never