10 Azure Kubernetes Service Interview Questions and Answers

Azure Kubernetes Service (AKS) is a managed container orchestration service that simplifies deploying, managing, and scaling containerized applications using Kubernetes. As organizations increasingly adopt microservices architectures and containerization, proficiency in AKS has become a valuable skill for IT professionals. AKS integrates seamlessly with other Azure services, providing a robust platform for building and maintaining scalable applications.

This article offers a curated selection of interview questions designed to test your knowledge and expertise in AKS. By reviewing these questions and their detailed answers, you will be better prepared to demonstrate your understanding of AKS concepts and best practices, enhancing your readiness for technical interviews.

Azure Kubernetes Service Interview Questions and Answers

1. Explain the purpose of Kubernetes manifests and how they are used in AKS.

Kubernetes manifests act as blueprints for Kubernetes resources, defining the desired state of applications, including replicas, container images, and networking configurations. In Azure Kubernetes Service (AKS), these manifests are used to deploy and manage applications, ensuring the cluster’s state aligns with the defined specifications. A typical manifest for deploying an application might specify a deployment with multiple replicas, each running a container from a specified image. To apply this manifest in AKS, use the kubectl apply command to create or update the resources, ensuring the AKS cluster matches the desired state.

2. Describe the different types of Services in Kubernetes and their use cases in AKS.

In Kubernetes, services define a logical set of pods and a policy for accessing them. In AKS, there are four primary types of services:

• ClusterIP: Exposes the service on an internal IP within the cluster, used for internal communication.
• NodePort: Exposes the service on each node’s IP at a static port, accessible from outside the cluster, useful for development and testing.
• LoadBalancer: Exposes the service externally using a cloud provider’s load balancer, commonly used for production workloads.
• ExternalName: Maps a service to a DNS name, used to proxy requests to an external service outside the Kubernetes cluster.

3. Explain how to integrate Azure Monitor with AKS for monitoring and logging purposes.

Azure Monitor provides enhanced monitoring and logging for AKS, offering insights into cluster performance and health. To integrate Azure Monitor with AKS, enable monitoring during cluster creation or install the Azure Monitor for containers agent on existing clusters. Configure a Log Analytics workspace to store and analyze data, and view metrics and logs in the Azure portal. Azure Monitor offers dashboards and visualizations for analysis and allows for custom alerts and queries.

4. Describe the process of setting up a CI/CD pipeline for AKS using Azure DevOps.

Setting up a CI/CD pipeline for AKS using Azure DevOps involves several steps:

1. Create a Project: Start by creating a new project in Azure DevOps.

2. Set Up a Repository: Create a Git repository to store application code.

3. Configure Build Pipeline: Automate the build process, including tasks like restoring dependencies, compiling code, running tests, and creating Docker images.

4. Push Docker Images to ACR: Push Docker images to Azure Container Registry (ACR) for deployment to AKS.

5. Set Up a Release Pipeline: Automate the deployment of applications to AKS, using Kubernetes manifests or Helm charts.

6. Trigger Pipelines: Configure triggers to start pipelines based on events like code commits.

7. Monitor and Manage: Use Azure DevOps and AKS tools to track pipeline and deployment status.

5. Explain how the Horizontal Pod Autoscaler (HPA) works in AKS and when you would use it.

The Horizontal Pod Autoscaler (HPA) in AKS automatically scales the number of pod replicas based on observed metrics like CPU utilization. HPA queries resource utilization against specified metrics and adjusts replicas accordingly. This dynamic scaling is useful for applications with variable workloads, ensuring optimal performance and resource utilization. For example, an e-commerce site might use HPA to handle fluctuating traffic, scaling out during peak times and scaling in during low traffic periods.

6. Provide the steps to implement Network Policies in AKS to restrict traffic between pods.

Network Policies in AKS control traffic between pods, enhancing security and isolation. To implement Network Policies, ensure your AKS cluster supports them, define policies using YAML files, and apply them with kubectl apply. Verify the policies by testing pod communication.

Example of a NetworkPolicy YAML file:

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: allow-specific-traffic
  namespace: default
spec:
  podSelector:
    matchLabels:
      app: myapp
  policyTypes:
  - Ingress
  - Egress
  ingress:
  - from:
    - podSelector:
        matchLabels:
          app: allowed-app
  egress:
  - to:
    - podSelector:
        matchLabels:
          app: allowed-app

7. Explain the cost optimization strategies you can use to manage expenses in an AKS environment.

Cost optimization in AKS involves strategies like right-sizing resources, implementing auto-scaling, using Spot Instances for non-critical workloads, managing node pools, setting resource quotas, and leveraging Azure’s cost management tools. Consider using Reserved Instances for long-term workloads to save costs.

8. What are some best practices for securing an AKS cluster?

Securing an AKS cluster involves best practices like implementing network policies, using RBAC for permissions, managing secrets, enforcing pod security policies, keeping components updated, and using monitoring tools. Employ Network Security Groups, use trusted container images, and enable encryption for data security.

9. How do you perform upgrades and maintenance on an AKS cluster?

Upgrading and maintaining an AKS cluster involves planning the upgrade, upgrading the control plane and node pools, and monitoring the cluster post-upgrade. Regular maintenance tasks include applying security patches and updating configurations. Use Azure tools to automate and manage these tasks.

10. Discuss how AKS integrates with other Azure services like Azure Active Directory and Azure DevOps.

Azure Active Directory (AAD) Integration:
AKS integrates with Azure Active Directory for secure authentication and authorization, managing user access through role-based access control (RBAC).

Azure DevOps Integration:
AKS integrates with Azure DevOps to streamline CI/CD pipelines, automating application deployment to Kubernetes clusters and supporting DevOps practices like infrastructure as code and automated rollbacks.