How to Create and Configure Ingress in Kubernetes¶

This guide explains how to implement and manage Ingress resources in Kubernetes for routing external HTTP/HTTPS traffic to your services.

Prerequisites¶

Running Kubernetes cluster
NGINX Ingress Controller installed
Basic understanding of DNS and HTTP routing
(Optional) cert-manager for SSL/TLS certificates

What is Ingress?¶

Ingress exposes HTTP and HTTPS routes from outside the cluster to services within the cluster. Traffic routing is controlled by rules defined on the Ingress resource.

Key features: - Path-based routing - Host-based routing - SSL/TLS termination - Load balancing - Name-based virtual hosting

Basic Ingress Configurations¶

1. Simple Path-based Routing¶

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: simple-routing
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /
spec:
  ingressClassName: nginx
  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

Apply and verify:

kubectl apply -f simple-ingress.yaml
kubectl get ingress simple-routing

Output:

NAME             CLASS   HOSTS   ADDRESS          PORTS   AGE
simple-routing   nginx   *       192.168.1.100    80      30s

2. Host-based Routing¶

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: host-routing
spec:
  ingressClassName: nginx
  rules:
  - host: app1.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: app1-service
            port:
              number: 80
  - host: app2.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: app2-service
            port:
              number: 80

Check the status:

kubectl describe ingress host-routing

Output:

Name:             host-routing
Namespace:        default
Address:          192.168.1.100
Default backend:  default-http-backend:80 (<error: endpoints "default-http-backend" not found>)
Rules:
  Host              Path  Backends
  ----              ----  --------
  app1.example.com  
                    /   app1-service:80 (10.244.0.23:80)
  app2.example.com  
                    /   app2-service:80 (10.244.0.24:80)
Events:
  Type    Reason  Age   From                      Message
  ----    ------  ----  ----                      -------
  Normal  CREATE  45s   nginx-ingress-controller  Ingress default/host-routing

Advanced Configurations¶

1. SSL/TLS Configuration¶

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: tls-example
  annotations:
    cert-manager.io/cluster-issuer: "letsencrypt-prod"
spec:
  ingressClassName: nginx
  tls:
  - hosts:
    - secure.example.com
    secretName: example-tls
  rules:
  - host: secure.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: secure-service
            port:
              number: 80

Check TLS status:

kubectl get certificate example-tls

Output:

NAME          READY   SECRET        AGE
example-tls   True    example-tls   2m

2. Rate Limiting¶

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: rate-limit
  annotations:
    nginx.ingress.kubernetes.io/limit-rps: "10"
    nginx.ingress.kubernetes.io/limit-connections: "5"
spec:
  ingressClassName: nginx
  rules:
  - host: api.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: api-service
            port:
              number: 80

3. Session Persistence¶

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: sticky-session
  annotations:
    nginx.ingress.kubernetes.io/affinity: "cookie"
    nginx.ingress.kubernetes.io/session-cookie-name: "route"
    nginx.ingress.kubernetes.io/session-cookie-expires: "172800"
    nginx.ingress.kubernetes.io/session-cookie-max-age: "172800"
spec:
  ingressClassName: nginx
  rules:
  - host: app.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: web-service
            port:
              number: 80

Production Examples¶

1. Multi-domain Application¶

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: multi-domain
  annotations:
    cert-manager.io/cluster-issuer: "letsencrypt-prod"
    nginx.ingress.kubernetes.io/proxy-body-size: "50m"
    nginx.ingress.kubernetes.io/proxy-connect-timeout: "60"
spec:
  ingressClassName: nginx
  tls:
  - hosts:
    - api.example.com
    - web.example.com
    secretName: multi-domain-tls
  rules:
  - host: api.example.com
    http:
      paths:
      - path: /v1
        pathType: Prefix
        backend:
          service:
            name: api-v1-service
            port:
              number: 80
      - path: /v2
        pathType: Prefix
        backend:
          service:
            name: api-v2-service
            port:
              number: 80
  - host: web.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: web-service
            port:
              number: 80

Check multi-domain status:

kubectl get ingress multi-domain -o wide

Output:

NAME           CLASS   HOSTS                           ADDRESS         PORTS     AGE
multi-domain   nginx   api.example.com,web.example.com 192.168.1.100  80, 443  1m

Monitoring and Troubleshooting¶

1. Check Ingress Status¶

kubectl describe ingress <ingress-name>

Example Output:

Name:             web-ingress
Namespace:        default
Address:          192.168.1.100
Default backend:  default-http-backend:80
Rules:
  Host        Path  Backends
  ----        ----  --------
  *           /     web-service:80 (10.244.0.25:80)
Annotations:  nginx.ingress.kubernetes.io/rewrite-target: /
Events:
  Type    Reason  Age   From                      Message
  ----    ------  ----  ----                      -------
  Normal  CREATE  1m    nginx-ingress-controller  Ingress default/web-ingress

2. View Ingress Controller Logs¶

kubectl logs -n ingress-nginx -l app.kubernetes.io/name=ingress-nginx

Example Output:

I0923 10:20:30.123456       7 event.go:282] Event(v1.ObjectReference{Kind:"Ingress", ...})
I0923 10:20:30.234567       7 controller.go:155] Configuration changes detected, backend reload required
I0923 10:20:30.345678       7 controller.go:172] Backend successfully reloaded

3. Test Ingress Rules¶

# Using curl
curl -H "Host: app.example.com" http://<ingress-ip>/path

Example Output:

HTTP/1.1 200 OK
Server: nginx/1.21.1
Date: Mon, 23 Sep 2025 10:20:35 GMT
Content-Type: application/json
Content-Length: 42

{"message": "Successfully accessed through Ingress"}

Best Practices¶

Always use TLS in production
Implement rate limiting for APIs
Set appropriate timeouts
Use proper health checks
Monitor Ingress controller metrics

Troubleshooting Common Issues¶

404 Not Found
Check service name and port
Verify path configuration
Check if service endpoints exist
502 Bad Gateway
Check if backend pods are running
Verify service selectors
Check pod health
SSL Certificate Issues
Verify cert-manager configuration
Check certificate status
Ensure DNS records are correct

Next Steps¶

Set up monitoring and alerting
Implement canary deployments
Configure WAF rules
Set up automated testing
Implement blue-green deployments