You write a Lambda function that needs to connect to an RDS MySQL database. You use a CD pipeline to deploy the Lambda function in the same VPC subnet as the RDS database so that they can communicate. However, you find that the deployed Lambda function is not able to connect to the internet. How would you resolve this problem?

Answer options:

A.Modify the pipeline to deploy the Lambda function in the default VPC rather than the same VPC as RDS.
B.Configure a NAT gateway in the VPC and route the outbound traffic to the NAT gateway.
C.Deploy the Lambda function outside of the custom VPC.D.Open the outgoing port in the Lambda function access control list.

Correct Answer – B
Option A is incorrect: Because the Lambda function cannot communicate with the RDS database if it is in a different VPC.Option B is CORRECT: When the Lambda function is in a VPC, the VPC needs to access the internet. The NAT gateway has a public IP address and connects to the internet.
Option C is incorrect: Because the Lambda function will lose the connection with the RDS database if it is outside of the VPC.Option D is incorrect: Because the Lambda function does not have an access control list. In this scenario, VPC should have internet access.
Reference:
https://docs.aws.amazon.com/lambda/latest/dg/configuration-vpc.html