Question 29
Domain 3: Design High-Performing ArchitecturesSebuah perusahaan menjalankan aplikasi web dengan backend di banyak EC2 instances. Mereka butuh load balancer yang bisa: - Route berdasarkan **path URL** (`/api/*` ke satu target group, `/images/*` ke target group lain) - Support **WebSocket connections** - **Health check** per target group Load balancer mana yang paling tepat?
Correct answer: C
Explanation
Application Load Balancer is designed for Layer 7 routing, so it can route by URL path such as "/api/*" and "/images/*" to different target groups. The source notes ALB under "Load balancing concepts" and "Layer 7," which also supports WebSocket connections and health checks per target group.
Why each option is right or wrong
A. Classic Load Balancer (CLB)
B. Network Load Balancer (NLB)
C. **Application Load Balancer (ALB)**
ALB is the Layer 7 load balancer in AWS, and the exam material explicitly places it under load balancing concepts for path-based routing. In this scenario, it can inspect the HTTP request path and forward `/api/*` and `/images/*` to different target groups, while still performing target-group health checks on each group. It also supports WebSocket traffic over HTTP/HTTPS, which fits the web application requirement better than a Layer 4 balancer.
D. Gateway Load Balancer (GWLB)