Answer-first summary for fast verification
Answer: Deploy a NAT gateway. Associate an Elastic IP address with the NAT gateway. Configure the VPC to use the NAT gateway.
1. **Explanation for Answer A:** Deploying a NAT gateway is the correct solution because it allows instances within a private subnet (like the Lambda function in this case) to access the internet while keeping their IP addresses private. Here's how it works: - A NAT (Network Address Translation) gateway is a managed network service in AWS that performs the translation of private IP addresses to public IP addresses. - By associating an Elastic IP address with the NAT gateway, the Lambda function can access the internet through this single public IP address. - The VPC configuration is updated to route traffic destined for the internet through the NAT gateway. This ensures that all outbound traffic from the Lambda function to the external provider will appear to come from the public IP address of the NAT gateway, which can be added to the external provider's allow list. 2. **Why other options are incorrect:** - Option B: An egress-only internet gateway is used for IPv6 traffic and is not suitable for providing a single public IP address for IPv4 traffic. - Option C: Configuring the Lambda function to use an internet gateway directly is not possible as Lambda functions do not have direct access to an internet gateway. - Option D: While deploying an internet gateway and associating an Elastic IP address is possible, configuring the default route in the public VPC route table to use the internet gateway does not address the requirement of providing a single public IP address for the Lambda function, which resides in a private subnet. The Lambda function needs a NAT gateway to translate its private IP address to the public IP address associated with the NAT gateway.
Author: LeetQuiz Editorial Team
Ultimate access to all questions.
No comments yet.
A company is building a serverless application that runs on an AWS Lambda function that is attached to a VPC. The company needs to integrate the application with a new service from an external provider. The external provider supports only requests that come from public IPv4 addresses that are in an allow list. The company must provide a single public IP address to the external provider before the application can start using the new service. Which solution will give the application the ability to access the new service?
A
Deploy a NAT gateway. Associate an Elastic IP address with the NAT gateway. Configure the VPC to use the NAT gateway.
B
Deploy an egress-only internet gateway. Associate an Elastic IP address with the egress-only internet gateway. Configure the elastic network interface on the Lambda function to use the egress-only internet gateway.
C
Deploy an internet gateway. Associate an Elastic IP address with the internet gateway. Configure the Lambda function to use the internet gateway.
D
Deploy an internet gateway. Associate an Elastic IP address with the internet gateway. Configure the default route in the public VPC route table to use the internet gateway.