What types of AWS load balancers are there, and how do they relate to Kubernetes?
Quick Answer
ALB (layer 7, HTTP/HTTPS, path/host routing), NLB (layer 4, TCP/UDP, ultra-low latency and static IPs), and the legacy CLB. In Kubernetes/EKS, a Service type LoadBalancer provisions an NLB/ALB, and an Ingress controller (AWS Load Balancer Controller) provisions an ALB.
Detailed Answer
Pick ALB for HTTP routing, TLS termination, and WAF integration; NLB for raw TCP/UDP, extreme performance, or preserving client IP. On EKS the AWS Load Balancer Controller maps Ingress to ALBs (one ALB fronting many services) and Service type LoadBalancer to NLBs — consolidating at the ALB via Ingress is usually cheaper than one LB per service.
Interview Tip
Map ALB=L7/HTTP, NLB=L4/performance, and note Ingress+ALB consolidates many services behind one LB — cost awareness scores well.