CKAD 試験問題を無料オンラインアクセス

You are running a multi-tier application in Kubernetes. Your application consists of a frontend service (nginx) and a backend service (app). The frontend service exposes a port to the outside world, while the backend service listens on a different port. The backend service needs to access a database service running on a different node.
You need to create a network policy that allows the nginx service to access the app service, and the app service to access the database service. Ensure tnat no otner traffic is allowed between pods in the cluster.

正解：

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
1. Define Network Policy for Nginx Service:
- Create a NetworkPoliCY named 'nginx-policy' that allows traffic from pods labeled 'app=nginx' to pods labeled Sapp-apps
- Use 'ingress' rules to define incoming traffic to the nginx service-
- Specify the for the nginx service.
- Allow all ports.

2. Define Network Policy for App Service: - Create a NetworkP01iCY named 'app-policy' that allows traffic from pods labeled 'app=app' to pods labeled 'app=database' - Use 'ingress' rules to define incoming traffic to the app service. - Specify the 'podSeIector' for the app service. - Allow traffic on the port that the database service listens on.

3. Create the NetworkPolicy Objects - Apply the NetworkP01iCies using the 'kubectl apply' command: bash kubectl apply -f nginx-policy.yaml kubectl apply -f app-policy.yaml 4. Apply Default Network Policy: - Create a NetworkPoliCY named 'default-policy' that blocks all traffic by default. - This ensures that only traffic allowed by the specific policies is permitted.

5. Apply Default Network Policy: - Apply the NetworkPoliCY using the 'kubectl apply' command: bash kubectl apply -f default-policy_yaml This configuration ensures that: - Nginx Service: Can access the 'app' service on port 80, and no other traffic is allowed in or out. - App Service: Can access the 'database' service on port 5432, and no other traffic is allowed in or out - All Other Pods: All other pods in the cluster are blocked from communicating with each other by the default network policy.,

You have a stateful application that requires persistent storage. You need to create a PersistentV01umeClaim (PVC) that Will be used by a Deployment to store application dat a. The PVC should have the following specifications:
- Access Modes: ReadWriteOnce
- Storage Class: 'fast-storage
- Storage Size: IOGi
Provide the YAML code for creating this PVC.

正解：

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
1. create the PVC YAML file:

2. Apply the PVC YAML using kubectl: bash kubectl apply -f my-pvc.yaml 3. Verify the PVC creatiom bash kubectl get pvc You should see the PVC ' my-pvc' listed with the specified access mode, storage class, and size.,

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?

正解：

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 Deployment running with a specific image tag, and you want to roll out a new version with a different image tag- However, you want to ensure that the update process is gradual, and only one pod is updated at a time. Additional'" you need to monitor the performance metrics of the application during the update, and if the performance degrades significantly, you need to rollback to the previous version How would you implement this using Kustomize and other Kubernetes features?

正解：

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
1. Create a customization file:
resources :
- deployment. yaml
2. Create a deployment-yaml file:

3. Configure a rolling update strategy: - Edit the 'deployment.yamr file and add the following to the 'spec-strategy' section:

4. Set up monitoring with Prometheus and Grafana: - Install Prometheus and Grafana on your Kubernetes cluster. - Configure Prometheus to scrape metrics from your application pods. - Create Grafana dashboards to visualize the relevant metrics. 5. Create an alert in Prometheus: - Define an alert that triggers if the application's performance degrades significantly - This alert should be configured to send notifications to your team. 6. Create a rollback mechanism: - IJse a script or a tool like 'oubect1 rollout undo' to rollback the deployment to the previous version if the performance alert is triggered. 7. Update the deployment with the new image tag: - Edit the 'deployment-yamp file and change the 'image' to 'example/nginx:v2 8. Apply the changes to your Kubernetes cluster: bash oubect1 apply -f deployment-yaml - The 'maxSurge' and 'maxunavailable' settings in the 'rollinglJpdate' strategy control the maximum number of pods that can be added or removed during the update process. - Prometheus and Grafana provide a way to monitor the performance metrics of your application. - The Prometheus alert helps you identify if the performance degrades significantly during the update process. - The rollback mechanism allows you to revert to the previous version if the performance alert is triggered. - This setup ensures a gradual update process and provides a mechanism to mitigate potential performance issues. ,

You are tasked With setting up a Kubernetes cluster With a service that exposes a web application, along with a database running as a stateful set The application needs to access the database through an internal IP address, but the database should not be accessible from outside the cluster. What are the steps involved to configure this, and what components should be used to achieve this setup?

正解：

See the solution below with Step by Step Explanation.
Explanation:
Solution (Step by Step) :
I). Create the Database StatefuISet:
- Define a StatefulSet for your database, ensuring it uses a persistent volume to store its data.
- Specify the database image and any necessary configuration.
- Configure a service of type 'ClusterlP' for the database, accessible only within the cluster

2. Create the Application Deployment: - Create a Deployment for your web application, specifying the application image and required ports. - Add an environment variable to the application container to define tne database connection string, using the database service's ClusterlP.

3. Create the Application Service: - Create a service of type 'LoadBalancers (or 'NodePort' if using a cloud provider) for your web application, exposing it to the outside world. - Ensure the service points to the application deployment.

4. Verify the Setup: - Ensure all resources are created successfully by running 'kubectl get all' - Access the web application through the external IP address exposed by the LoadBalancer service. - Verify that tne application can connect to the database. By following these steps, you've created a secure setup where the database is only accessible from within the cluster, while your web application can communicate With the database and expose its services to the outside world. , You have a Kubernetes cluster with multiple namespaces: 'dev', 'staging', and 'production'. You need to implement a network policy that allows pods in the 'dev' namespace to access services running in the 'staging' namespace. POdS in the 'dev' namespace should only be allowed to connect to ports 80 and 443 on the services in the 'staging' namespace. Implement the network policy configuration. A. See the solution below with Step by Step Explanation. Answer: A