SAA-C03 Question 538
Single answerA company has an application running in a private subnet within a VPC. The application needs to download software updates from the internet but does not require inbound connections from the internet. The company is evaluating whether to use a NAT instance or a NAT gateway to enable this connectivity. Which of the following is the most cost-effective solution for a production environment with consistent traffic volumes?
- A
Use a NAT instance with an On-Demand EC2 instance and scale it based on traffic patterns.
- B
Use a NAT gateway and pay for its hourly usage and data processing costs.
- C
Use a NAT instance with a Reserved EC2 instance to reduce cost in a production environment.
- D
Use a NAT gateway only during peak traffic hours and stop it during off-peak hours.
Show answer and explanation
Correct answer: B
Explanation
For a production environment with consistent traffic, a NAT gateway is the better choice. It is fully managed, highly available, and eliminates the operational overhead associated with managing a NAT instance. Although NAT instances might be cheaper in some scenarios, they require more effort to manage and scale, making them less suitable for a production use case.
- A. Incorrect.
Using a NAT instance requires managing the instance, including scaling and monitoring its performance. While cost savings might be achieved by scaling, this approach is not ideal for consistent traffic in production environments due to operational overhead.
- B. Correct.
A NAT gateway is a fully managed service that is highly available and scalable. While it has higher hourly costs compared to a NAT instance, it eliminates operational overhead, making it a better choice for consistent traffic in production environments.
- C. Incorrect.
While using a Reserved EC2 instance for a NAT instance reduces costs compared to On-Demand pricing, it still requires management and does not offer the scalability and availability provided by a NAT gateway.
- D. Incorrect.
NAT gateways cannot be started and stopped like EC2 instances. They are billed continuously while provisioned, so this option is invalid.