Linux Foundation CKA Exam Dumps

Solution:

solution

Step 0: Set the correct Kubernetes context

If you're given a specific context (k8s in this case), you must switch to it:

kubectl config use-context k8s

Skipping this can cause you to work in the wrong cluster/namespace and cost you marks.

Step 1: Identify the namespace of the pod foo

First, check if foo is running in a specific namespace or in the default namespace.

kubectl get pods --all-namespaces | grep foo

Assume the pod is in the default namespace if no namespace is mentioned.

Step 2: Confirm pod foo exists and is running

kubectl get pod foo

You should get output similar to:

NAME READY STATUS RESTARTS AGE

foo 1/1 Running 0 1h

If the pod is not running, logs may not be available.

Step 3: View logs and filter specific error lines

We're looking for log lines that contain:

unable-to-access-website

Command:

kubectl logs foo | grep 'unable-to-access-website'

Step 4: Write the filtered log lines to a file

Redirect the output to the required path:

kubectl logs foo | grep 'unable-to-access-website' > /opt/KULM00201/foo

This creates or overwrites the file /opt/KULM00201/foo with the filtered logs.

You may need sudo if /opt requires elevated permissions. But in most exam environments, you're already the root or privileged user.

Step 5: Verify the output file (optional but smart)

Check that the file was created and has the correct content:

cat /opt/KULM00201/foo

Final Answer Summary:

kubectl config use-context k8s

kubectl logs foo | grep 'unable-to-access-website' > /opt/KULM00201/foo

kubectl get po nginx -o

jsonpath='{.spec.containers[].image}{'\n'}'

Task Summary

Connect to host cka000056

Review existing frontend and backend Deployments

Choose one correct NetworkPolicy from the ~/netpol directory

The policy must:

Allow traffic only from the frontend Deployment to the backend Deployment

Avoid being overly permissive

Apply the correct NetworkPolicy without modifying any sample files

Step-by-Step Instructions

Step 1: SSH into the correct node

ssh cka000056

Step 2: Inspect the frontend Deployment

Check the labels used in the frontend Deployment:

kubectl get deployment -n frontend -o yaml

Look under metadata.labels or spec.template.metadata.labels. Note the app or similar label (e.g., app: frontend).

Step 3: Inspect the backend Deployment

kubectl get deployment -n backend -o yaml

Again, find the labels assigned to the pods (e.g., app: backend).

Step 4: List and review the provided NetworkPolicies

List the available files:

ls ~/netpol

Check the contents of each policy file:

cat ~/netpol/<file-name>.yaml

Look for a policy that:

Has kind: NetworkPolicy

Applies to the backend namespace

Uses a podSelector that matches the backend pods

Includes an ingress.from rule that references the frontend namespace using a namespaceSelector (and optionally a podSelector)

Does not allow traffic from all namespaces or all pods

Here's what to look for in a good match:

apiVersion: networking.k8s.io/v1

kind: NetworkPolicy

metadata:

name: allow-frontend-to-backend

namespace: backend

spec:

podSelector:

matchLabels:

app: backend

ingress:

- from:

- namespaceSelector:

matchLabels:

name: frontend

Even better if the policy includes:

- namespaceSelector:

matchLabels:

name: frontend

podSelector:

matchLabels:

app: frontend

This limits access to pods in the frontend namespace with a specific label.

Step 5: Apply the correct NetworkPolicy

Once you've identified the best match, apply it:

kubectl apply -f ~/netpol/<chosen-file>.yaml

Apply only one file. Do not alter or delete any existing sample.

ssh cka000056

kubectl get deployment -n frontend -o yaml

kubectl get deployment -n backend -o yaml

ls ~/netpol

cat ~/netpol/*.yaml # Review carefully

kubectl apply -f ~/netpol/<chosen-file>.yaml

Command Summary

ssh cka000056

kubectl get deployment -n frontend -o yaml

kubectl get deployment -n backend -o yaml

ls ~/netpol

cat ~/netpol/*.yaml # Review carefully

kubectl apply -f ~/netpol/<chosen-file>.yaml

// create a pod

kubectl run nginx --image=nginx --restart=Never --port=80

// List the pod with different verbosity

kubectl get po nginx --v=7

kubectl get po nginx --v=8

kubectl get po nginx --v=9