CKA Practice Exam: Part 3

1. Use the following command to create the YAML for your deployment:

   kubectl create deployment webfront-deploy  --image=nginx:1.7.8  --dry-run -o yaml > webfront-deploy.yaml
   

2. Add container port 80, to have your final YAML look like this:

   apiVersion: apps/v1
   kind: Deployment
   metadata:
     creationTimestamp: null
     labels:
       app: webfront-deploy
     name: webfront-deploy
   spec:
     replicas: 1
     selector:
       matchLabels:
         app: webfront-deploy
     strategy: {}
     template:
       metadata:
         creationTimestamp: null
         labels:
           app: webfront-deploy
       spec:
         containers:
         - image: nginx:1.7.8
           name: nginx
           resources: {}
           ports:
           - containerPort: 80
   status: {}
   

3. Use the following command to create your deployment:

   kubectl apply -f webfront-deploy.yaml
   

4. Use the following command to scale up your deployment:

   kubectl scale deployment/webfront-deploy --replicas=2
   

5. Use the following command to create the YAML for a service:

   kubectl expose deployment/webfront-deploy --port=80 --target-port=80 --type=NodePort --dry-run -o yaml > webfront-service.yaml
   

6. Add the name and the nodePort, the complete YAML will look like this:

   apiVersion: v1
   kind: Service
   metadata:
     creationTimestamp: null
     labels:
       app: webfront-deploy
     name: webfront-service
   spec:
     ports:
     - port: 80
       protocol: TCP
       targetPort: 80
       nodePort: 30080
     selector:
       app: webfront-deploy
     type: NodePort
   status:
     loadBalancer: {}
   

7. Use the following command to create the service:

   kubectl apply -f webfront-service.yaml
   

8. Verify that you can communicate with your pod directly:

   kubectl run busybox --rm -it --image=busybox /bin/sh
   
   # wget -O- <pod_ip_address>:80
   # wget --spider --timeout=1 webfront-service
   

Use the following command to create a Redis pod:

kubectl run db-redis --image=redis --restart=Never

1. Use the following YAML (this is where you can use kubernetes.io and search "network policies" and then search for the text "default"):

   apiVersion: networking.k8s.io/v1
   kind: NetworkPolicy
   metadata:
     name: default-deny
   spec:
     podSelector: {}
     policyTypes:
     - Ingress
   

2. Use the following command to apply the network policy:

   kubectl apply -f default-deny.yaml
   

3. Verify that communication has been disabled by default:

   kubectl run busybox --rm -it --image=busybox /bin/sh
   # wget -O- ≤pod_ip_address>:80
   

1. Use the following commands to apply the labels:

   kubectl get po
   kubectl label po <pod_name> role=frontend
   kubectl label po db-redis role=db
   kubectl get po --show-labels
   

2. Use the following YAML to create a network policy for the communication between the two labeled pods (copy from kubernetes.io website):

   apiVersion: networking.k8s.io/v1
   kind: NetworkPolicy
   metadata:
     name: redis-netpolicy
   spec:
     podSelector:
       matchLabels:
         role: db
     ingress:
     - from:
       - podSelector:
           matchLabels:
             role: frontend
       ports:
       - port: 6379
   

3. Use the following command to create the network policy:

   kubectl apply -f redis-netpolicy.yaml
   

4. Use the following command to view the network policies:

   kubectl get netpol
   

5. Use the following command to describe the custom network policy:

   kubectl describe netpol redis-netpolicy
   

6. Use the following command to show the labels on the pods:

   kubectl get po --show-labels