Kubernetes Deployment: Two-Path Ingress Routing on EKS via Kubernetes Ingress Route Paths

In modern cloud-native applications, efficient routing of incoming traffic is crucial for optimal performance and user experience. Kubernetes Ingress, especially when combined with Amazon Elastic Kubernetes Service (EKS), offers a powerful and flexible way to manage external access to your services. This article delves into a specific and powerful configuration: two-path Ingress routing on EKS using Kubernetes Ingress Route Paths. We’ll explore the concepts, benefits, and a step-by-step guide to implementing this configuration.

Table of Contents

1. Introduction to Kubernetes Ingress and EKS
   • What is Kubernetes Ingress?
   • Benefits of using Ingress
   • Amazon EKS Overview
2. Understanding Ingress Controllers
   • What are Ingress Controllers?
   • Popular Ingress Controllers (NGINX, Traefik, AWS Load Balancer Controller)
   • Choosing the Right Ingress Controller
3. Two-Path Ingress Routing: Concepts and Benefits
   • What is Two-Path Ingress Routing?
   • Use Cases for Two-Path Routing
   • Benefits of Implementing Two-Path Routing
4. Setting up EKS Cluster
   • Prerequisites
   • Creating an EKS Cluster using `eksctl`
   • Configuring `kubectl` to connect to your EKS Cluster
5. Deploying Sample Applications
   • Creating Deployment and Service definitions for two applications
   • Applying the Deployment and Service definitions
   • Verifying the application deployment
6. Configuring Ingress with Route Paths
   • Installing the AWS Load Balancer Controller
   • Creating an Ingress resource with path-based routing
   • Understanding the Ingress resource configuration
7. Testing the Ingress Configuration
   • Obtaining the Load Balancer DNS Name
   • Accessing the applications via the specified paths
   • Verifying the routing behavior
8. Advanced Configuration and Considerations
   • TLS/SSL Termination
   • Custom Annotations and Configuration
   • Monitoring and Logging
9. Troubleshooting Common Issues
   • Ingress Controller not functioning
   • Path routing not working as expected
   • SSL/TLS certificate issues
10. Best Practices for Ingress Management on EKS
    • Security Considerations
    • Scalability and Performance Optimization
    • Automation and Infrastructure as Code (IaC)
11. Conclusion

1. Introduction to Kubernetes Ingress and EKS

What is Kubernetes Ingress?

Kubernetes Ingress is an API object that manages external access to services within a Kubernetes cluster. It acts as a single entry point, exposing multiple services through a single IP address. Ingress rules define how traffic should be routed to different backend services based on the host name or path in the request. Think of it as a reverse proxy or a smart router for your Kubernetes services.

Benefits of using Ingress

• Centralized Access: Provides a single entry point for all external traffic, simplifying routing and management.
• Path-Based Routing: Allows routing traffic to different services based on the URL path.
• Host-Based Routing: Allows routing traffic based on the hostname in the request.
• TLS/SSL Termination: Can handle TLS/SSL encryption and decryption, offloading this task from the backend services.
• Load Balancing: Distributes traffic across multiple instances of a service for improved performance and availability.
• Simplified Configuration: Reduces the complexity of managing multiple load balancers.

Amazon EKS Overview

Amazon Elastic Kubernetes Service (EKS) is a managed Kubernetes service that makes it easy to run Kubernetes on AWS without needing to install, operate, and maintain your own Kubernetes control plane. EKS automates critical tasks like upgrades, patching, and scaling, freeing you to focus on building and deploying your applications.

2. Understanding Ingress Controllers

What are Ingress Controllers?

An Ingress Controller is a specific implementation that fulfills the Ingress resource definition. It is a component running within your Kubernetes cluster that interprets the Ingress resource and configures the underlying infrastructure (like a load balancer) to route traffic accordingly. Without an Ingress Controller, the Ingress resource itself is just a configuration specification.

Popular Ingress Controllers

• NGINX Ingress Controller: A widely used and highly performant Ingress Controller based on the popular NGINX web server and reverse proxy. It’s flexible, configurable, and supports a wide range of features.
• Traefik: A modern Ingress Controller designed for dynamic environments like Kubernetes. It automatically discovers services and configures itself based on your Kubernetes resources.
• AWS Load Balancer Controller: Specifically designed for EKS, this controller provisions and manages AWS Application Load Balancers (ALBs) in response to Ingress resources. This is the controller we will be using in this tutorial.

Choosing the Right Ingress Controller

The best Ingress Controller for your needs depends on your specific requirements and environment. Consider the following factors:

• Ease of Use: How easy is it to configure and manage?
• Performance: How well does it handle traffic?
• Features: Does it support the features you need (e.g., TLS/SSL, custom annotations)?
• Integration: Does it integrate well with your existing infrastructure?
• Community Support: How active is the community and how readily available is documentation and support?

3. Two-Path Ingress Routing: Concepts and Benefits

What is Two-Path Ingress Routing?

Two-path Ingress routing, also known as path-based routing, is a configuration where incoming traffic is routed to different backend services based on the URL path specified in the request. For example, requests to `/app1` might be routed to application A, while requests to `/app2` are routed to application B. This allows you to expose multiple applications or services through a single domain name and IP address.

Use Cases for Two-Path Routing

• Microservices Architecture: Route traffic to different microservices based on the path.
• Versioned APIs: Route traffic to different versions of an API (e.g., `/v1`, `/v2`).
• Multiple Applications on a Single Domain: Host multiple applications or websites on the same domain, differentiating them by path.
• A/B Testing: Route a portion of traffic to a new version of an application for testing purposes.
• Content Management Systems (CMS): Route different content types to different backend systems (e.g., `/blog` to a blog platform, `/shop` to an e-commerce platform).

Benefits of Implementing Two-Path Routing

• Simplified Infrastructure: Reduces the need for multiple load balancers and external IPs.
• Cost Savings: Conserves resources and reduces infrastructure costs.
• Improved Organization: Provides a clear and logical structure for routing traffic.
• Enhanced Security: Easier to manage security policies and access control.
• Flexibility: Allows you to easily add or modify routes without affecting other services.

4. Setting up EKS Cluster

Prerequisites

Before you begin, ensure you have the following prerequisites:

• AWS Account: An active AWS account with appropriate permissions.
• AWS CLI: The AWS Command Line Interface installed and configured. Ensure it has the necessary permissions to manage EKS and related resources.
• `kubectl`:** The Kubernetes command-line tool installed and configured.
• `eksctl`:** A command-line tool for creating and managing EKS clusters. Install it from eksctl.io.
• IAM Role for your AWS user: Ensure your AWS user has sufficient IAM Role to be able to manage EKS, EC2 and other related services.

eksctl create cluster --name my-cluster --region us-west-2

aws eks update-kubeconfig --name my-cluster --region us-west-2

kubectl get nodes

apiVersion: apps/v1
kind: Deployment
metadata:
  name: app1-deployment
  labels:
    app: app1
spec:
  replicas: 2
  selector:
    matchLabels:
      app: app1
  template:
    metadata:
      labels:
        app: app1
    spec:
      containers:
      - name: app1
        image: nginx:latest
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: app1-service
spec:
  selector:
    app: app1
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
  type: ClusterIP

apiVersion: apps/v1
kind: Deployment
metadata:
  name: app2-deployment
  labels:
    app: app2
spec:
  replicas: 2
  selector:
    matchLabels:
      app: app2
  template:
    metadata:
      labels:
        app: app2
    spec:
      containers:
      - name: app2
        image: nginx:latest
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: app2-service
spec:
  selector:
    app: app2
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
  type: ClusterIP

kubectl apply -f app1-deployment.yaml
kubectl apply -f app2-deployment.yaml

kubectl get deployments
kubectl get services

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: my-ingress
  annotations:
    kubernetes.io/ingress.class: alb
    alb.ingress.kubernetes.io/scheme: internet-facing
    alb.ingress.kubernetes.io/target-type: ip
spec:
  rules:
  - http:
      paths:
      - path: /app1
        pathType: Prefix
        backend:
          service:
            name: app1-service
            port:
              number: 80
      - path: /app2
        pathType: Prefix
        backend:
          service:
            name: app2-service
            port:
              number: 80

kubectl apply -f ingress.yaml

kubectl get ingress my-ingress

alb.ingress.kubernetes.io/certificate-arn: arn:aws:acm:YOUR_REGION:YOUR_ACCOUNT_ID:certificate/YOUR_CERTIFICATE_ID

alb.ingress.kubernetes.io/scheme: internet-facing

alb.ingress.kubernetes.io/scheme:  https