AWS Certified Advanced Networking Specialty Practice Exam

When configuring a new endpoint for Amazon S3 in a VPC without Internet connectivity, what is a common requirement for successful connections?

1. Route entry in the subnet route table

2. Direct connection to an Internet Gateway

3. Public IP for VPC instances

4. Additional IAM user accounts

The correct answer is: Route entry in the subnet route table

When configuring a new endpoint for Amazon S3 in a VPC without Internet connectivity, having a route entry in the subnet route table is essential for successful connections. This route entry directs traffic destined for Amazon S3 to the VPC endpoint rather than to the Internet. Without this route, requests from instances within the VPC would not be able to reach the S3 service, leading to failures in connectivity. When you add a VPC endpoint for S3, it creates a private connection between your VPC and S3 without requiring that traffic go through the Internet. The route table must have an entry that points to the VPC endpoint for S3, ensuring that any traffic intended for S3 is appropriately routed through the endpoint. This setup effectively allows the VPC resources to reach S3 privately and securely while maintaining the requirement that there is no direct Internet access. The other options, while they may pertain to networking principles, do not specifically address the isolation requirement of VPC configurations within AWS for accessing S3 endpoints without Internet connectivity.