AWS Certified Solutions Architect – Associate (SAA-C02) — Question 169

A company is concerned that two NAT instances in use will no longer be able to support the traffic needed for the company's application. A solutions architect wants to implement a solution that is highly available fault tolerant, and automatically scalable.
What should the solutions architect recommend?

Answer options

• A. Remove the two NAT instances and replace them with two NAT gateways in the same Availability Zone.
• B. Use Auto Scaling groups with Network Load Balancers for the NAT instances in different Availability Zones.
• C. Remove the two NAT instances and replace them with two NAT gateways in different Availability Zones.
• D. Replace the two NAT instances with Spot Instances in different Availability Zones and deploy a Network Load Balancer.

Correct answer: C

Explanation

The correct answer is C because using NAT gateways in different Availability Zones ensures higher availability and fault tolerance, as they can handle traffic independently. Option A does not provide high availability since both NAT gateways are in the same Availability Zone, while B focuses on Auto Scaling for instances, which is unnecessary for NAT functions. Option D introduces Spot Instances, which are not reliable for consistent NAT services due to their potential termination.