Why Kubernetes manages microservice deployment in Microservices - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a Kubernetes deployment for a microservice.

Microservices

kubectl create deployment [1] --image=myapp:latest

Drag options to blanks, or click blank then click option'

Amy-microservice

Bservice

Cpod

Dcontainer

Attempts:

3 left

💡 Hint

Common Mistakes

Using generic terms like 'service' or 'pod' instead of a unique deployment name.

The deployment name should be a unique identifier for your microservice, such as 'my-microservice'.

2fill in blank

medium

Complete the command to expose the microservice deployment as a service.

Microservices

kubectl expose deployment my-microservice --type=[1] --port=80

Drag options to blanks, or click blank then click option'

AClusterIP

BLoadBalancer

CNodePort

DExternalName

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing ClusterIP which is internal only.

NodePort exposes the service on each Node's IP at a static port, making it accessible externally.

3fill in blank

hard

Fix the error in the YAML snippet to define a container image for the microservice.

Microservices

containers:
  - name: my-microservice
    image: [1]

Drag options to blanks, or click blank then click option'

Amyapp:latest

Bmyapp_latest

Cmyapp/latest

Dmyapp-latest

Attempts:

3 left

💡 Hint

Common Mistakes

Using slashes or underscores instead of colon in image tag.

The correct image format uses a colon ':' to separate the image name and tag, like 'myapp:latest'.

4fill in blank

hard

Fill both blanks to complete the YAML for a Kubernetes service selector.

Microservices

selector:
  app: [1]
  tier: [2]

Drag options to blanks, or click blank then click option'

Afrontend

Bbackend

Cmy-microservice

Ddatabase

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up app and tier labels or using unrelated labels.

The selector matches pods labeled with app: my-microservice and tier: frontend to route traffic correctly.

5fill in blank

hard

Fill all three blanks to complete the command for scaling the deployment.

Microservices

kubectl scale deployment [1] --replicas=[2] --namespace=[3]

Drag options to blanks, or click blank then click option'

Amy-microservice

B5

Cproduction

Ddefault

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong deployment name, replica count, or namespace.

This command scales the 'my-microservice' deployment to 5 replicas in the 'production' namespace.

Practice

1. Why does Kubernetes manage microservice deployment instead of manually running each service?

easy

A. Because it replaces the need for any servers

B. Because it automates starting, stopping, and scaling services reliably

C. Because it writes the code for microservices automatically

D. Because it only works with one service at a time

Solution

1. Step 1: Understand manual deployment challenges

   Manually running many microservices is hard to keep track of and scale.

2. Step 2: Role of Kubernetes in deployment

   Kubernetes automates managing service lifecycles, scaling, and recovery to keep apps running smoothly.

3. Final Answer:

   Because it automates starting, stopping, and scaling services reliably -> Option B

4. Quick Check:

   Automation of service management = B [OK]

Hint: Kubernetes automates service control, not replaces servers or code [OK]

Common Mistakes:

• Thinking Kubernetes replaces servers
• Believing Kubernetes writes app code
• Assuming Kubernetes handles only one service

2. Which of the following is the correct Kubernetes command to deploy a microservice from a YAML file named service.yaml?

easy

A. kubectl apply -f service.yaml

B. kubectl run service.yaml

C. kubectl start service.yaml

D. kubectl create service.yaml

Solution

1. Step 1: Identify the command to apply configuration files

   The kubectl apply -f command applies changes from a YAML file to the cluster.

2. Step 2: Check other options for correctness

   kubectl run is for running pods directly, kubectl start and kubectl create do not accept YAML files directly.

3. Final Answer:

   kubectl apply -f service.yaml -> Option A

4. Quick Check:

   Apply YAML file = kubectl apply -f [OK]

Hint: Use 'kubectl apply -f' to deploy YAML files [OK]

Common Mistakes:

• Using 'kubectl run' to deploy YAML files
• Trying 'kubectl start' which is invalid
• Confusing 'kubectl create' with applying configs

3. Given this Kubernetes YAML snippet for a microservice pod:

apiVersion: v1
kind: Pod
metadata:
  name: myservice
spec:
  containers:
  - name: app
    image: myapp:v1
    ports:
    - containerPort: 80

What will happen if the pod crashes unexpectedly?

medium

A. The pod will restart only if the image is updated

B. The pod will stay crashed until manually restarted

C. Kubernetes will automatically restart the pod to keep the service running

D. Kubernetes will delete the pod and not recreate it

Solution

1. Step 1: Understand pod restart policy default

   By default, Kubernetes restarts pods automatically if they crash to maintain service availability.

2. Step 2: Check other options for correctness

   Pods do not stay crashed without restart, nor are they deleted permanently without recreation, and restarts are not tied to image updates.

3. Final Answer:

   Kubernetes will automatically restart the pod to keep the service running -> Option C

4. Quick Check:

   Pod auto-restart on crash = D [OK]

Hint: Pods auto-restart by default to keep services alive [OK]

Common Mistakes:

• Thinking pods stay crashed until manual restart
• Believing pods delete permanently on crash
• Assuming restart depends on image updates

4. You deployed a microservice with Kubernetes, but it keeps crashing. The YAML file has this snippet:

spec:
  containers:
  - name: app
    image: myapp:v1
    ports:
    - containerPort: 80
  restartPolicy: Never

What is the problem and how to fix it?

medium

A. The pod name is missing; add metadata name

B. The containerPort is wrong; change it to 8080

C. The image version is invalid; update to 'v2'

D. The restartPolicy 'Never' stops restarts; change it to 'Always' to fix

Solution

1. Step 1: Identify restartPolicy effect

   Setting restartPolicy: Never means Kubernetes will not restart the pod if it crashes.

2. Step 2: Fix by changing restartPolicy

   Changing restartPolicy to Always lets Kubernetes restart the pod automatically to keep it running.

3. Final Answer:

   The restartPolicy 'Never' stops restarts; change it to 'Always' to fix -> Option D

4. Quick Check:

   restartPolicy 'Always' enables auto-restart [OK]

Hint: Use restartPolicy 'Always' to auto-restart pods [OK]

Common Mistakes:

• Changing port without checking crash cause
• Updating image version without error info
• Ignoring restartPolicy effect

5. You want to deploy a microservice that must always be available, even if some pods fail. Which Kubernetes feature helps achieve this and how?

hard

A. Use a Deployment with replicas to run multiple pod copies for high availability

B. Use a single Pod with restartPolicy set to Never

C. Use a ConfigMap to store pod data for recovery

D. Use a ServiceAccount to control pod permissions

Solution

1. Step 1: Understand high availability needs

   Running multiple copies of a microservice ensures it stays available if some pods fail.

2. Step 2: Use Kubernetes Deployment with replicas

   A Deployment manages multiple pod replicas and automatically replaces failed pods to maintain availability.

3. Final Answer:

   Use a Deployment with replicas to run multiple pod copies for high availability -> Option A

4. Quick Check:

   Deployment + replicas = high availability [OK]

Hint: Deploy replicas with Deployment for service uptime [OK]

Common Mistakes:

• Using single pod with no replicas
• Confusing ConfigMap with availability
• Mixing permissions with availability