AKS – 20 – What is different between Load balancer in service and ingress.

LoadBalancer Service:

• Think of it like giving each dish its own waiter.
• Every app (service) gets its own entrance and dedicated staff.
• Simple and direct: one app = one public IP.
• Good for small menus (few apps).

🧾 Example: You have one app (welcome-app) and want to expose it to the internet. You use LoadBalancer, and your cloud provider gives you a public IP to access it directly.

🛎️ Ingress:

• Think of it like a smart receptionist at the front desk.
• One entrance, but the receptionist routes guests to the right table based on what they ask for.
• You can serve many dishes (apps) through one public IP.
• Great for big menus (many apps or microservices).

🧾 Example: You have multiple apps like welcome-app, admin-app, and api-service. Instead of giving each one a separate IP, you use Ingress to route:

• / → welcome-app
• /admin → admin-app
• /api → api-service

🔍 Summary Table

Feature	LoadBalancer	Ingress
External IP	One per service	One for all services
Cost	Higher (more IPs/load balancers)	Lower (shared IP)
Routing	Basic (just forwards traffic)	Smart (path/host-based)
TLS/HTTPS	Manual setup	Built-in support
Best for	Simple/single app	Multiple apps, microservices

✅ When to Use What?

• Use LoadBalancer if:
  • You have one or two services.
  • You want quick and simple external access.
  • You don’t need advanced routing.
• Use Ingress if:
  • You have multiple services.
  • You want to save costs.
  • You need routing, TLS, or custom domains.

multiple types of Ingress Controllers,

1. NGINX Ingress Controller

• Most widely used and community-supported.
• Great for general-purpose routing.
• Supports path-based and host-based routing, TLS, rate limiting, etc.
• Easy to set up and works well in most environments.

✅ Best for: Simplicity, flexibility, and community support.

2. Traefik

• Modern, dynamic, and cloud-native.
• Auto-discovers services and updates routes in real-time.
• Built-in dashboard, metrics, and Let’s Encrypt support.

✅ Best for: Dynamic environments, microservices, and real-time updates.

Istio Ingress Gateway

• Part of the Istio service mesh.
• Offers advanced traffic management, security, and observability.
• More complex to set up.

✅ Best for: Enterprises using service mesh and needing fine-grained control.