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AWS EKS  All About With Interview Questions

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Nahidul Islam
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5 min read

Amazon EKS simplifies the deployment, management, and scaling of containerized applications using Kubernetes on AWS. It removes the complexities associated with setting up and running Kubernetes clusters, allowing developers and DevOps teams to focus more on application development and less on infrastructure management.

Key Features and Benefits

1. Fully Managed Kubernetes Control Plane: Amazon EKS provides a fully managed control plane that is highly available, automatically patched, and scalable, ensuring reliability and security without operational overhead.

2. Integration with AWS Services: EKS seamlessly integrates with various AWS services like Elastic Load Balancing, IAM, VPC, and others, enabling efficient utilization of the AWS ecosystem.

3. Security and Compliance: It adheres to AWS security best practices and offers features like encryption, IAM authentication, and network isolation to ensure robust security and compliance.

4. Scalability and High Availability: EKS enables automatic scaling of clusters based on workload demands and provides built-in redundancy for high availability.

EKS Nodes (Worker Nodes) Registered with the Control Plane

EKS nodes, or worker nodes, are EC2 instances or AWS Fargate pods that execute the containerized applications (pods) within the Kubernetes cluster. These nodes are registered with the EKS control plane

AWS Fargate on EKS

AWS Fargate is a serverless compute engine for containers that allows users to run containers without managing the underlying infrastructure. In the context of EKS, Fargate can be used as an alternative to traditional EC2 instances for running pods.

  1. Question: Explain the architecture of an AWS EKS cluster and its components.

    Answer: An AWS EKS cluster consists of the EKS control plane managed by AWS, worker nodes running in an Auto Scaling Group, and the AWS networking infrastructure, typically using Amazon VPC and subnets. For instance, the control plane includes the API server, scheduler, and etcd, while worker nodes run Kubernetes pods.

  2. Question: How does AWS EKS handle security and node access?

    Answer: AWS EKS provides IAM integration and AWS IAM roles for Kubernetes service accounts, ensuring secure authentication and authorization to AWS resources. For example, by associating IAM roles with Kubernetes service accounts, pods can securely access AWS services without explicit credentials.

  3. Question: Explain the significance of AWS EKS and how it differs from self-managed Kubernetes clusters.

    Answer: AWS EKS is a managed Kubernetes service by AWS, offering automated updates, scalability, and integration with AWS services. Unlike self-managed clusters, EKS abstracts infrastructure management tasks, allowing focus on application development. For example, with EKS, AWS manages the control plane, while in self-managed clusters, all aspects require manual upkeep, including patching, scaling, and maintenance.

  4. Question: How does AWS EKS handle the deployment of worker nodes?

    Answer: AWS EKS facilitates worker node deployment through the EKS Managed Node Group. For instance, by creating an EKS Node Group, I can specify instance types, networking settings, and scaling configurations, allowing EKS to manage and scale the worker nodes based on demand.

  5. Question: How does AWS EKS handle node scaling and auto-healing in response to increased workloads or node failures?

    Answer: AWS EKS leverages the Kubernetes Cluster Autoscaler to manage node scaling based on resource utilization. Additionally, using AWS Auto Scaling Groups, I've configured EKS worker nodes to automatically scale in or out based on CPU/memory metrics or custom CloudWatch alarms. This ensures efficient resource utilization and availability in response to workload changes.

  6. Question: How does AWS EKS manage Kubernetes control plane upgrades?

    Answer: AWS EKS automates Kubernetes control plane upgrades. For example, AWS EKS schedules automatic upgrades for the control plane to the latest Kubernetes version, ensuring minimal disruption to running workloads and maintaining cluster stability.

  7. Question: Discuss the networking architecture options available in AWS EKS and their advantages.

    Answer: AWS EKS offers networking through Amazon VPC CNI (Container Networking Interface) and Kubenet. For example, Amazon VPC CNI enables each Kubernetes pod to have an AWS network interface, providing better networking performance and security compared to Kubenet, which uses a simpler networking model but with fewer features.

  8. Question: Explain how you would update the Kubernetes version in an AWS EKS cluster.

    Answer: Upgrading Kubernetes versions in EKS involves creating a new EKS cluster with the desired Kubernetes version and migrating workloads. For instance, I'd create a new cluster with the updated version, deploy applications, test, and gradually migrate traffic to the new cluster before decommissioning the old one.

  9. Question: How do you integrate AWS IAM roles with Kubernetes pods in EKS?

    Answer: AWS IAM roles can be mapped to Kubernetes service accounts in EKS using IAM Roles for Service Accounts (IRSA). For example, by associating an IAM role with a Kubernetes service account, pods can assume AWS IAM roles to access AWS services securely.

  10. Question: Discuss the high-availability features and best practices when designing an AWS EKS cluster.

    Answer: AWS EKS supports multi-AZ (Availability Zone) deployment for control plane components, ensuring high availability. For example, deploying worker nodes across multiple AZs, utilizing Auto Scaling Groups, and leveraging AWS features like Application Load Balancers for ingress routing ensures high availability in an EKS cluster.

  11. Question: Explain the process of integrating AWS CloudWatch with AWS EKS for monitoring and logging.

    Answer: AWS EKS can integrate with AWS CloudWatch for logging and monitoring Kubernetes workloads. For example, by setting up the CloudWatch agent on worker nodes, logs can be sent to CloudWatch Logs for central storage and monitoring using CloudWatch Metrics and Dashboards.

  12. Question: How does AWS EKS manage Kubernetes control plane components, and what role does it play in cluster management?

    Answer: AWS EKS abstracts the management of Kubernetes control plane components such as the API server, etcd, and scheduler. AWS fully manages these components, ensuring high availability, scalability, and reliability of the Kubernetes control plane. For instance, when scaling an EKS cluster, AWS automatically manages the scaling of these control plane components, relieving users from manual management tasks.

  13. Question: Explain the process of deploying applications onto an AWS EKS cluster.

    Answer: Applications are deployed on AWS EKS clusters using Kubernetes manifests (YAML files) defining deployment, services, and pods. Using kubectl apply or CI/CD pipelines like Jenkins, I'd deploy containerized applications onto the EKS cluster.