Online Access Free CKAD Practice Test

You have a Deployment for a web application that uses a separate Redis cache pod for session management. You want to ensure that each web application pod can access a dedicated Redis instance for session management and avoid contention. Explain how you can use a PersistentVolumeClaim and StatetulSet to achieve this.

Correct Answer:

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
I). Create a PersistentVoIumeClaim:
- Create a PersistentVoIumeCIaim (PVC) to request persistent storage for each Redis instance.
- Specify the storage size, access modes, and other requirements based on your needs.
- Example:

2. Create a StatefulSet: - Define a StatefulSet for the Redis pods. - Associate each Redis pod with a unique PVC, ensuring that each pod gets its own dedicated persistent volume. - Example:

3. Configure the Deployment: - Denne tne web application pod Within a Deployment. - Use a Service (e.g., 'redis-service') to access the Redis instances. - Make sure the web application's code can access the Redis instances using the service name. - Example:

4. Deploy and Test - Deploy tne PersistentVolumeClaim, StatefulSet, and Deployment. - Test the web application to ensure that each pod can access its own dedicated Redis instance and session data is correctly managed Without contention. 5. Important: - StatefulSets ensure that each pod has a unique hostname and persistent storage, making them suitable for managing stateful applications. - This approach helps isolate Redis instances, preventing session data conflicts and ensuring the scalability of your web application. ,

You are deploying a microservice application consisting of three components: 'frontend' , 'backend' , and 'database'. You want to ensure that the 'backend' service is deployed only after the 'frontend' service has successfully started and is healthy. Additionally, the 'database' service should be deployed only after the 'backend' service is ready. How would you implement this deployment strategy using Kubernetes deployments?

Correct Answer:

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
1. Define Pre-requisites for Services:
- Create a 'Deployment for each service (frontend', 'backend', and 'database').
- For the 'backend' service, define a 'pre-requisite' in the 'dependencies' section of the 'Deployment' object, specifying that the ' frontend' service needs to be healthy and running. This can be achieved using the 'dependson' field in the 'spec.template.spec_containers' section of the Deployment.
- Similarly, for the 'database service, define a Tre-requisite' specifying that the 'backend' service needs to be healthy and running.
- Example 'frontend' Deployment:

- Example 'backend' Deployment:

- Example 'database' Deployment:

2. Create the Deployments: - Apply the YAML files using 'kubectl apply -f frontend-deployment.yamr , 'kubectl apply -f backend-deployment.yamr , and 'kubectl apply -f database- deployment-yaml. 3. Monitor the Deployment Process: - use 'kubectl get pods -l app=frontend' , 'kubectl get pods -l app=backend' , and 'kubectl get pods -l app=database' to monitor the deployment of the pods. - You will observe that the 'frontend' pods will start first, followed by the 'backend' pods after the 'frontend' pods are healthy. Finally, the 'database' pods will start after the 'backend' pods are healthy. 4. Verify the Deployment Success: - Use 'kubectl describe deployments frontend-deployment', 'kubectl describe deployments backend-deployment , and 'kubectl describe deployments database-deployment' to verify the successful deployment of each service. - Confirm that the 'Ready' status of each pod is true. This strategy ensures that the services are deployed in a predictable and reliable order, ensuring the application's integrity and functionality.,

You have a container image that uses a specific version of a library. You want to update this library to a newer version while still keeping the previous version available for compatibility purposes. Describe the steps involved in modifying the container image to include both versions of the library without rebuilding the entire application.

Correct Answer:

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
1. Create a Dockerfile:
- Create a new 'Dockerfile' with the following content:

- Replace 'your-library' Witn the actual library name. - Replace 'new-version' and 'old-version' witn tne desired versions. 2. Build the Image: - Build the image using tne DockerTlle: docker build -t updated-image:latest 3. Modify your application code: - Modify your application code to explicitly import the specific version of the library that you want to use. For example: python # Import the new version for new functionality from your_library impon new_functionality # Import the Old version for backward compatibility from your_library import old_functionality # Use the appropriate version of the library based on your requirements 4. IJpdate the Deployment - Modify your Deployment YAML file to use the newly built image:

5. Apply the Changes: - Apply the updated Deployment using kubectl apply -f deployment.yamr 6. Test the Application: - Access your application and ensure it functions correctly with both versions of the library.

You have a microservices application where you need to route traffic to different versions of a service based on the 'version' header in the incoming request. For example, if the header is set to 'VI' , the request should be routed to the 'VI' version Of the service, and if it's 'v? , it should be routed to the 'v? version. Design and implement an Ambassador pattern in Kubernetes to achieve this dynamic routing.

Correct Answer:

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
1. Create Ambassador Service and Deployment:
- Define an Ambassador service and deployment using the Ambassador chart
- The chart can be found at: https:ngithub.com/datawire/ambassador
- IJpdate the chart to include the Ambassador configuration for dynamic routing based on the 'version' header

2. Configure Ambassador for Header-Based Routing: - Update the Ambassador YAML configuration to define a mapping that uses the 'version' header for routing. - This configuration will specify the mapping from the header value to the corresponding service endpoint.

3. Deploy the Ambassador Configuration: - Create a ConfigMap or Secret in Kubernetes to store the Ambassador configuration- - Then, apply this configuration to your Ambassador deployment. 4. Create the Service Versions: - You need to have separate deployments and services for each version of your application. - Each version will have a unique service name to be referenced in the Ambassador configuration.

5. Test the Routing: - Send requests to the Ambassador service with different 'Version' headers. - Observe the traffic being routed correctly to the corresponding version of the service. bash curl -H 'Version: VI" http://ambassador-service-ip:8080/ curl -H 'Version: v2" http://ambassador-service-ip:8080/ This will route requests to the appropriate service version based on the 'Version' header.,

You have a Kubernetes deployment named 'wordpress-deployment' running multiple instances of a WordPress application. You want to implement a rolling update strategy with a 'maxSurge' of 1 and 'maxi-Jnavailable' of O. Additionally, you need to ensure that the update process is automatically triggered when a new image is pushed to the Docker Hub repository 'wordpress-image:latests. Implement a Kustomization file to achieve this.

Correct Answer:

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
1. Create a 'kustomization.yamr file in your desired directory.

2. Create a 'deployment-yamr file (or use an existing one) with the following structure.

3. Create a 'patch.yamr file with the following content to configure rolling update and automatic updates:

4. Apply the Kustomization: bash kubectl apply -k - The 'kustomization.yaml file defines the resources (the 'deployment.yamr file) and the patches to apply. - The 'deployment.yamr file contains the base configuration for the deployment. - The 'patch.yamr file applies a strategic merge patch to the deployment, configuring rolling updates and automatic updates triggered by new images. - The 'maxSurgew and 'maxunavailable' settings in the 'patch.yamr define the maximum number ot pods that can be added or removed during the update process. - The 'imagePullPolicy: AlwayS ensures that the new image is pulled from Docker Hub even if it exists in the pod's local cache, triggering the update.