AWS Certified Solutions Architect – Associate (SAA-C03) — Question 251

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 that the solution is highly available and fault tolerant. Option A does not provide high availability since both NAT gateways would be in the same Availability Zone. Option B suggests using Auto Scaling with NAT instances, which is unnecessary, as NAT gateways are designed to automatically scale. Option D introduces unnecessary complexity with Spot Instances, which are not ideal for NAT services.