Ingress vs LoadBalancer Service decision in Kubernetes - Hands-On Comparison

Ingress vs LoadBalancer Service Decision in Kubernetes

📖 Scenario: You are managing a Kubernetes cluster for a small company. You need to expose your web application to users outside the cluster. You want to decide whether to use an Ingress resource or a LoadBalancer service type to route external traffic to your application.

🎯 Goal: Build a simple Kubernetes configuration to understand the difference between using an Ingress and a LoadBalancer service. You will create a basic service and deployment, then add either a LoadBalancer service or an Ingress resource to expose the app externally. This will help you learn when to choose each option.

📋 What You'll Learn

Create a deployment named webapp with one replica running the nginx image

Create a service named webapp-service exposing port 80

Add a LoadBalancer service type to expose the app externally

Add an Ingress resource to route traffic to the service

Understand the difference in configuration and usage between LoadBalancer and Ingress

💡 Why This Matters

🌍 Real World

In real Kubernetes clusters, exposing applications to users outside the cluster is common. Choosing between LoadBalancer services and Ingress resources affects cost, flexibility, and features.

💼 Career

DevOps engineers and cloud administrators must understand how to expose services securely and efficiently. Knowing when to use LoadBalancer or Ingress is essential for managing Kubernetes networking.

1

Create a Deployment for the web application

Create a Kubernetes deployment named webapp with one replica running the nginx image. Use port 80 in the container spec.

Kubernetes

# Create a deployment named webapp with 1 replica running nginx on port 80
# Your code here

Need a hint?

Use kind: Deployment and set replicas: 1. The container should use the nginx image and expose port 80.

2

Create a Service to expose the Deployment internally

Create a Kubernetes service named webapp-service that selects pods with label app: webapp. Expose port 80 and target port 80. Use service type ClusterIP.

Kubernetes

apiVersion: apps/v1
kind: Deployment
metadata:
  name: webapp
spec:
  replicas: 1
  selector:
    matchLabels:
      app: webapp
  template:
    metadata:
      labels:
        app: webapp
    spec:
      containers:
      - name: nginx
        image: nginx
        ports:
        - containerPort: 80

# Create a ClusterIP service named webapp-service exposing port 80
# Your code here

Need a hint?

Use kind: Service with type: ClusterIP. Match pods with label app: webapp. Expose port 80.

3

Change the Service type to LoadBalancer to expose externally

Modify the webapp-service service to use type: LoadBalancer instead of ClusterIP. Keep all other settings the same.

Kubernetes

apiVersion: apps/v1
kind: Deployment
metadata:
  name: webapp
spec:
  replicas: 1
  selector:
    matchLabels:
      app: webapp
  template:
    metadata:
      labels:
        app: webapp
    spec:
      containers:
      - name: nginx
        image: nginx
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: webapp-service
spec:
  selector:
    app: webapp
  ports:
  - protocol: TCP
    port: 80
    targetPort: 80
  # Change service type to LoadBalancer below
  # Your code here

Need a hint?

Change the type field in the service spec to LoadBalancer to expose the service externally.

4

Create an Ingress resource to route traffic to the Service

Create a Kubernetes Ingress resource named webapp-ingress that routes HTTP traffic from host example.com to the webapp-service on port 80. Use the nginx ingress class.

Kubernetes

apiVersion: apps/v1
kind: Deployment
metadata:
  name: webapp
spec:
  replicas: 1
  selector:
    matchLabels:
      app: webapp
  template:
    metadata:
      labels:
        app: webapp
    spec:
      containers:
      - name: nginx
        image: nginx
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: webapp-service
spec:
  selector:
    app: webapp
  ports:
  - protocol: TCP
    port: 80
    targetPort: 80
  type: LoadBalancer

# Create an Ingress named webapp-ingress routing host example.com to webapp-service port 80
# Use nginx ingress class
# Your code here

Need a hint?

Use kind: Ingress with annotation kubernetes.io/ingress.class: nginx. Route host example.com to service webapp-service on port 80.