EKS Interview Questions and Answers

For EKS interviews, adjust your preparation to your experience level. Freshers should focus on basic EKS interview questions and answers. Experienced candidates should delve into advanced topics and scenario-based questions. Utilize EKS interview questions and answers PDFs for a comprehensive study guide suitable for both beginners and seasoned professionals\

  1. What is Amazon EKS?

    Amazon EKS is a service from AWS that simplifies the operation of Kubernetes clusters. It manages the Kubernetes control plane, which allows you to deploy and run containerized applications without handling the underlying infrastructure yourself.

  1. What are the essential components of Amazon EKS?
    • Control Plane: This is managed by AWS and includes critical components such as the Kubernetes API server and the scheduler.
    • Worker Nodes: These are EC2 instances that run your containers and communicate with the control plane to manage the container lifecycle.
  1. What is AWS’s responsibility in managing the Kubernetes control plane in EKS?

    AWS takes care of the Kubernetes control plane management in EKS. This includes handling updates, applying patches, and maintaining the high availability of the control plane, freeing you from these tasks.

  1. What steps are involved in setting up an EKS cluster?
    • Step 1: Create the EKS cluster using either the AWS Management Console, AWS CLI, or SDKs.
    • Step 2: Deploy EC2 instances as worker nodes and attach them to the EKS cluster.
    • Step 3: Configure these worker nodes with the necessary Kubernetes settings and authentication.
  1. How does EKS ensure high availability?

    EKS spreads the control plane across multiple Availability Zones (AZs). In the event of an AZ failure, the system automatically switches to another AZ. Worker nodes can also be distributed across AZs to enhance reliability.

  1. How does EKS handle the management of worker nodes?

    Worker node management in EKS is handled through the Kubernetes Node Controller, which works with Amazon EC2 to provision nodes. Additionally, Auto Scaling Groups are used to adjust the number of worker nodes based on demand.

  1. What is the process for scaling an EKS cluster?

    To scale an EKS cluster, you modify the number of worker nodes in the Auto Scaling Group linked to the cluster. Adjusting the desired number of nodes in this group will trigger automatic scaling.

  1. How does EKS manage updates and patches?

    EKS automatically manages updates and patches for the control plane. AWS carries out these updates in a controlled manner to ensure continuous availability and minimal disruption to your applications.

  1. Can EKS be integrated with other AWS services?

    Yes, EKS can work with various AWS services. For instance, you can integrate with IAM for managing access, use ECR for storing container images, CloudWatch for monitoring, and App Mesh for service mesh functionality.

  1. What security features does EKS provide?

    EKS incorporates multiple security measures, including integration with IAM, encryption for data at rest and in transit, network isolation via VPC, and Kubernetes RBAC for managing resource access.

  1. What distinguishes Amazon EKS from a self-managed Kubernetes cluster?

    Amazon EKS is a managed service where AWS oversees the control plane, including its maintenance and updates. In contrast, self-managed clusters require you to manually handle the setup, maintenance, and management of the control plane.

  1. How can you scale an application on EKS?

    Scaling applications in EKS can be achieved through Kubernetes Horizontal Pod Autoscaler (HPA) for adjusting pod numbers based on usage, and Cluster Autoscaler for modifying worker node quantities as needed.

  1. What role do Kubernetes Operators play in EKS?

    Kubernetes Operators extend Kubernetes functionality by managing complex stateful applications. They automate various aspects of application management, including deployment, scaling, and recovery.

  1. How does EKS manage container images?

    EKS integrates with Amazon ECR, a managed container registry service. ECR provides secure storage for container images, which EKS clusters can pull from when deploying containers.

  1. What methods can be used to monitor an EKS cluster?

    EKS clusters can be monitored using Amazon CloudWatch, which allows you to collect and analyze metrics, create alarms, and review logs for insights into the cluster’s performance.

  1. What is the function of Kubernetes Ingress in EKS?

    Kubernetes Ingress controls external access to services within a cluster by managing HTTP and HTTPS routing. It enables you to configure how traffic is directed to services in an EKS cluster.

  1. What advantages does using AWS Fargate with EKS offer?

    AWS Fargate is a serverless compute engine for containers that eliminates the need to manage infrastructure. Using Fargate with EKS reduces operational complexity and improves scalability and resource efficiency.

  1. How can communication within an EKS cluster be secured?

    Security can be maintained through network isolation within a VPC, using TLS for pod communication, and storing sensitive data securely with Kubernetes Secrets.

  1. What is EKS Anywhere?

    EKS Anywhere extends EKS capabilities to on-premises or other cloud environments by allowing you to run EKS-managed clusters outside of AWS, bringing EKS features to diverse infrastructure setups.

  1. What strategies can be used to ensure high availability for applications on EKS?

    High availability can be achieved by:

    • Distributing applications across multiple Availability Zones (AZs).
    • Using ReplicaSets or Deployments to maintain the required number of replicas.
    • Utilizing AWS Load Balancers to evenly distribute traffic across services.
  1. What are EKS Managed Node Groups?

    EKS Managed Node Groups simplify the management of worker nodes by letting you specify configurations like node count and instance types, with EKS handling the provisioning and management.

  1. How can you implement fine-grained access control in EKS?

    Fine-grained access control is implemented using Kubernetes RBAC, which allows you to define detailed roles, role bindings, and service accounts to control access to resources and actions within the cluster.

  1. What is the EKS Pod Identity Webhook, and how does it improve security?

    The EKS Pod Identity Webhook integrates IAM roles with Kubernetes service accounts, enhancing security by providing precise access control and reducing the need for long-lived AWS credentials within pods.

  1. How do you enable and configure multi-cluster networking in EKS?

    Multi-cluster networking can be set up using the Amazon VPC CNI plugin, which allows you to share a VPC across multiple EKS clusters, enabling communication between pods in different clusters via private IP addresses.

  1. What is the EKS Pod Security Policy Admission Controller?

    This is a Kubernetes feature that enforces security policies for pods, ensuring compliance with container runtime security, host filesystem access restrictions, and other security measures in EKS clusters.

  1. How can you perform blue-green deployments in EKS?

    Blue-green deployments in EKS involve creating two separate environments (blue and green) and using Kubernetes deployments and services along with load balancers to switch traffic between these environments during updates.

  1. What are DaemonSets in EKS, and how are they used?

    DaemonSets ensure that a specific pod runs on every node or selected nodes in the cluster. They are useful for deploying system services like log collectors or monitoring agents on all nodes.

  1. How are rolling updates and rollbacks managed in EKS?

    Rolling updates are managed by updating the Deployment resource with new configurations or images, while rollbacks can be done by reverting to previous versions using the deployment’s revision history.

  1. What is the Cluster Autoscaler, and how does it function in EKS?

    The Cluster Autoscaler adjusts the number of worker nodes in an EKS cluster based on resource needs. It monitors pending pods and scales the cluster size to optimize resource usage.

  1. How can AWS App Mesh be integrated with EKS?

    AWS App Mesh integrates with EKS by deploying Envoy proxies as sidecar containers and configuring App Mesh resources, such as virtual services and nodes, to manage traffic routing, observability, and security within the cluster.