Linux Foundation CKAD Dumps - Pass Certified Kubernetes Application Developer Exam in 2026

To find the broken pod and store its name and namespace to /opt/KDOB00401/broken.txt, you can use the kubectl get pods command and filter the output by the status of the pod.

kubectl get pods --field-selector=status.phase=Failed -o jsonpath='{.items[*].metadata.namespace}/{.items[*].metadata.name}' > /opt/KDOB00401/broken.txt

This command will list all pods with a status of Failed and output their names and namespaces in the format <namespace>/. The output is then written to the /opt/KDOB00401/broken.txt file.

To store the associated error events to a file /opt/KDOB00401/error.txt, you can use the kubectl describe command to retrieve detailed information about the pod, and the grep command to filter the output for error events.

kubectl describe pods --namespace | grep -i error -B5 -A5 > /opt/KDOB00401/error.txt

Replace and with the name and namespace of the broken pod you found in the previous step.

This command will output detailed information about the pod, including error events. The grep command filters the output for lines containing 'error' and also prints 5 lines before and after the match.

To fix the issue, you need to analyze the error events and find the root cause of the issue.

It could be that the application inside the pod is not running, the container image is not available, the pod has not enough resources, or the liveness probe configuration is incorrect.

Once you have identified the cause, you can take appropriate action, such as restarting the application, updating the container image, increasing the resources, or modifying the liveness probe configuration.

After fixing the issue, you can use the kubectl get pods command to check the status of the pod and ensure

Solution:

To allow a pod to send and receive traffic only to and from specific pods, you can use network policies in Kubernetes.

First, you will need to create a network policy that defines the allowed traffic. You can create a network policy yaml file with the following rules:

apiVersion: networking.k8s.io/v1

kind: NetworkPolicy

metadata:

name: newpod-network-policy

namespace: default

spec:

podSelector:

matchLabels:

app: kdsn00201-newpod

ingress:

- from:

- podSelector:

matchLabels:

app: web

- podSelector:

matchLabels:

app: storage

This policy will only allow incoming traffic to the pod with the label app=kdsn00201-newpod from pods with the label app=web or app=storage. If you have different labels on your web and storage pods please update the matchLabels accordingly.

Once you have created the network policy, you can apply it to the cluster by running the following command:

kubectl apply -f <network-policy-file>.yaml

This will apply the network policy to the cluster, and the newpod will only be able to send and receive traffic to and from the web and storage pods.

Please note that, NetworkPolicy resource is not available by default, you need to enable the NetworkPolicy feature on your Kubernetes cluster. This feature is enabled by default on some clusters and must be explicitly enabled on others. You can check if NetworkPolicy is available by running the command kubectl api-versions | grep networking

Also, you need to ensure that the pods that you want to allow traffic to and from are running on the same namespace.

0) SSH to the correct host

ssh ckad00044

(Optional sanity)

kubectl config current-context

kubectl get ns | grep rapid-goat

1) Inspect the Deployment and current container name

kubectl -n rapid-goat get deploy busybox

kubectl -n rapid-goat get deploy busybox -o jsonpath='{.spec.template.spec.containers[*].name}{'\n'}'

kubectl -n rapid-goat get deploy busybox -o jsonpath='{.spec.template.spec.containers[*].image}{'\n'}'

Note the current container name (likely something like busybox). We need to rename it to musl.

2) Edit the Deployment (best for renaming container)

Renaming a container is easiest with edit:

kubectl -n rapid-goat edit deploy busybox

In the editor, find:

spec:

template:

spec:

containers:

- name: <old-name>

image: <old-image>

Change it to:

- name: musl

image: busybox:musl

Save and exit.

3) Ensure the rollout happens and completes

kubectl -n rapid-goat rollout status deploy busybox

4) Verify the new Pod template is correct

Check the Deployment template:

kubectl -n rapid-goat get deploy busybox -o jsonpath='{.spec.template.spec.containers[0].name}{'\n'}{.spec.template.spec.containers[0].image}{'\n'}'

Check running Pods and the image actually used:

kubectl -n rapid-goat get pods -o wide

POD=$(kubectl -n rapid-goat get pods -l app=busybox -o jsonpath='{.items[0].metadata.name}' 2>/dev/null || true)

If you don't have that label selector, just pick a pod name from kubectl get pods and:

kubectl -n rapid-goat describe pod | sed -n '/Containers:/,/Conditions:/p'

Solution: