AWS EKS Architecture Overview: Key Components and Best Practices

What Is AWS EKS? 

AWS EKS is a fully managed service provided by Amazon Web Services, designed to facilitate the deployment, management, and scaling of containerized applications using Kubernetes, an open-source container orchestration tool. 

The core of EKS revolves around the idea of “clusters.” A cluster is a collection of nodes—virtual machines or physical servers—where your Kubernetes applications run. EKS removes the complexity of setting up and managing your own Kubernetes control plane, allowing you to focus on deploying and running your applications.

AWS EKS is a game-changer for developers and organizations that rely on Kubernetes for their container orchestration needs. It provides a scalable and highly available control plane that runs across multiple AWS availability zones, ensuring your applications remain operational and accessible even if one zone goes down.

4 Core Components of AWS EKS 

1. EKS Control Plane

The EKS Control Plane is a fundamental component of AWS EKS. It is responsible for managing the Kubernetes API server and the backend database. The control plane consists of multiple AWS-managed servers distributed across three AWS Availability Zones. This design ensures high availability and redundancy, reducing the risk of a single point of failure.

The control plane handles all the administrative tasks for your cluster. For instance, it monitors the health of your nodes, manages the networking between your pods, and regulates the communication between your worker nodes and the Kubernetes API.

The EKS Control Plane is fully managed by AWS, so you don’t have to worry about its setup, maintenance, or upgrades. You can focus on building your applications and let AWS handle the underlying Kubernetes operations.

2. ECS Data Plane

The ECS Data Plane is where your Kubernetes workloads—the applications and services you deploy—run. The data plane consists of Amazon EC2 instances, which serve as the worker nodes in your EKS clusters.

The ECS Data Plane is flexible and scalable. You can choose the instance type that best suits your workloads, and you can scale the number of instances up or down depending on your needs.

With the ECS Data Plane, you can also leverage native AWS services and features, such as Elastic Load Balancing for distributing traffic and Auto Scaling groups for managing the size of your worker node groups.

3. Fargate: Serverless Compute for Containers

Fargate is a serverless compute engine for containers offered by AWS. With Fargate, you don’t need to manage any underlying infrastructure. You only need to define your application requirements, such as CPU and memory, and Fargate takes care of the rest, including the allocation of resources and the scheduling of containers.

Fargate works seamlessly with AWS EKS, enabling you to run your Kubernetes applications without needing to manage EC2 instances. Fargate also simplifies the scaling of your applications. You can set up auto-scaling policies based on CPU and memory usage, and Fargate will automatically adjust the number of running containers to match the demand.

4. EKS Connector

The EKS Connector is a relatively new addition to the AWS EKS service. It’s a virtual appliance that you deploy in your cluster to connect it to the EKS console. With the EKS Connector, you can manage both your AWS and on-premises Kubernetes clusters from the same AWS console.

The EKS Connector brings the benefits of AWS’s fully managed control plane to your on-premises Kubernetes clusters, without needing to migrate your applications to the cloud.

EKS Architecture Overview 

Nodes and Pods

In AWS EKS, nodes and pods form the backbone of the cloud infrastructure. Nodes, which are essentially servers, can be either virtual (running on Amazon EC2 instances) or physical (running in an on-premises data center). On these nodes, you run pods—the smallest unit in the Kubernetes object model that you create or deploy.

Each pod encapsulates an application container (or a group of tightly-coupled containers), storage resources, a unique network IP, and options that dictate how the containers should run. This structure allows for easy scaling and automation, making AWS EKS an excellent solution for businesses with growing or fluctuating demands.

Kubernetes API Server

The Kubernetes API server is an integral component of the AWS EKS architecture. It serves as a bridge between various components, acting as a sort of control panel for the entire Kubernetes system. The API server exposes the Kubernetes API, through which all interaction with the Kubernetes system occurs.

In AWS EKS, the Kubernetes API is fully managed, meaning you don’t need to worry about scaling or maintaining the API servers yourself. This managed service also ensures that the API server remains secure and updated.

EKS Networking and Load Balancing

One of the strengths of AWS EKS lies in its robust networking and load balancing capabilities. AWS EKS supports Kubernetes native networking, allowing pods to have their own IP addresses and allowing for direct communication between pods without the need for network translation.

Additionally, AWS EKS leverages the power of AWS’s elastic load balancing, which automatically distributes incoming application traffic across multiple targets, such as Amazon EC2 instances, containers, and IP addresses. This aids in increasing the availability and fault tolerance of your applications, ensuring a smooth user experience.

Learn more in our detailed guide to AWS EKS networking (coming soon)

Storage Options with EKS

AWS EKS offers a wide range of storage options, catering to different needs. Ephemeral storage, data that is tied to the pod’s lifecycle, is ideal for temporary data that doesn’t need to be stored long-term.

For persistent storage, EKS supports Amazon Elastic Block Store (EBS), a high-performance block storage service designed for use with Amazon EC2 for both throughput and transaction-intensive workloads. 

EKS also supports Amazon Elastic File System (EFS), a simple, scalable, fully managed elastic NFS file system for use with AWS Cloud services and on-premises resources.

Security and Authentication in EKS

When it comes to security and authentication, AWS EKS employs a multi-layered approach. AWS Identity and Access Management (IAM) roles and Kubernetes Role Based Access Control (RBAC) work hand-in-hand to provide granular control over who can access the Kubernetes API and what resources they can manage.

Additionally, AWS EKS integrates with AWS Key Management Service (KMS) for envelope encryption of Kubernetes secrets, adding an extra layer of protection for sensitive data. With AWS EKS, you can rest assured that your applications and data are secure.

Learn more in our detailed guide to AWS EKS security (coming soon)

Best Practices for Building an Effective EKS Architecture 

Designing EKS Clusters

When designing EKS clusters, it’s crucial to consider both the current and future needs of your applications. Think about the workloads you plan to run and the expected traffic levels. If you anticipate significant fluctuations in demand, consider employing auto-scaling to ensure that your applications can scale up or down based on need.

Also, consider the placement of your nodes and the distribution of your pods. It’s often beneficial to spread them across multiple availability zones for high availability.

Managing EKS Updates and Upgrades

Staying updated with the latest EKS versions is vital for maintaining a secure and efficient environment. AWS provides regular updates for EKS, including new features, bug fixes, and security patches. However, updating and upgrading your clusters require careful planning and execution.

Before initiating an update or upgrade, ensure that your applications are compatible with the new version. Test the update in a non-production environment before deploying it in production. Also, monitor the update process and validate your applications’ functionality post-update.

Ensuring High Availability and Disaster Recovery

High availability and disaster recovery are paramount in any cloud environment. When using AWS EKS, leverage multiple availability zones to spread your nodes and pods. This distribution can help protect your applications from the failure of a single zone.

For disaster recovery, regularly backup your data using services like AWS Backup. In the event of a disaster, you can quickly restore your applications and data, minimizing downtime and loss.

Securing EKS Applications and Data

Securing your applications and data in EKS involves numerous best practices. Employ the principle of least privilege by limiting access to your Kubernetes API. Use AWS IAM and Kubernetes RBAC to control who can access what resources.

Encrypt sensitive data using AWS KMS and regularly audit your security configurations using AWS Security Hub. Also, consider using AWS Shield for DDoS protection and AWS WAF for web application firewall capabilities.

Monitoring and Observability for EKS Clusters

Monitoring and observability are critical aspects of managing AWS EKS clusters. The basic way to monitor EKS is with Amazon CloudWatch—CloudWatch collects monitoring and operational data from EKS clusters in the form of logs, metrics, and events. You can track the health and performance of your EKS clusters and receive notifications about any unusual activity or performance deviations.

As part of CloudWatch, AWS offers the Container Insights feature, which helps you monitor, troubleshoot, and alarm on your containerized environments. With Container Insights, you can access dashboards that summarize the performance and health of EKS and ECS clusters by services, tasks, pods, and containers.

However, to gain full observability for applications running in EKS, you’ll need a full cloud native observability solution. Lumigo is one such solution, which provides an in-depth view of how your applications are performing, how they’re interacting with other services, and actionable insights on improving uptime and performance.

AWS EKS with Lumigo

The distributed nature of containers (and microservices in general), whether running on AWS EKS, or another orchestrator, means that your applications will typically require more than just monitoring with metrics and logs. In order to keep an eye on the many different services these applications are composed of, distributed tracing is critical to keep applications up and running smoothly.

Lumigo is a cloud native observability platform that delivers automated distributed tracing, purpose-built for distributed applications, including those running on ECS and soon, EKS.

Lumigo provides deep visibility into applications and infrastructure with all the relevant information on each component, enabling you to easily monitor and troubleshoot container applications.

• Automatically correlate metrics, events and traces and delivers visualizations of end-to-end requests in one complete view
• Drill down into application performance and monitor clusters as well as underlying services in real-time
• Set up customized alerts in notification platforms (ie Slack) and go from alert to root cause in just a few clicks

Learn more about Lumigo