AWS Certified Solutions Architect – Associate (SAA-C02) — Question 345

A company hosts a website on premises and wants to migrate it to the AWS Cloud. The website exposes a single hostname to the internet but it routes its functions to different on-premises server groups based on the path of the URL. The server groups are scaled independently depending on the needs of the functions they support. The company has an AWS Direct Connect connection configured to its on-premises network.
What should a solutions architect do to provide path-based routing to send the traffic to the correct group of servers?

Answer options

• A. Route all traffic to an internet gateway. Configure pattern matching rules at the internet gateway to route traffic to the group of servers supporting that path.
• B. Route all traffic to a Network Load Balancer (NLB) with target groups for each group of servers. Use pattern matching rules at the NLB to route traffic to the correct target group.
• C. Route all traffic to an Application Load Balancer (ALB). Configure path-based routing at the ALB to route traffic to the correct target group for the servers supporting that path.
• D. Use Amazon Route 53 as the DNS server. Configure Route 53 path-based alias records to route traffic to the correct Elastic Load Balancer for the group of servers supporting that path.

Correct answer: C

Explanation

An Application Load Balancer (ALB) operates at Layer 7 and natively supports path-based routing, allowing it to inspect HTTP/HTTPS traffic and forward requests to specific target groups, which can include on-premises servers via AWS Direct Connect. Network Load Balancers (NLB) operate at Layer 4 and lack URL path-routing capabilities. Neither Internet Gateways nor Amazon Route 53 support routing traffic based on URL path rules.