Which solution will meet these requirements?
Implement an interface VPC endpoint for Amazon SQS. Configure the endpoint to use the private subnets. Add to the endpoint a security group that has an inbound access rule that allows traffic from the EC2 instances that are in the private subnets.
Implement an interface VPC endpoint for Amazon SQS. Configure the endpoint to use the public subnets. Attach to the interface endpoint a VPC endpoint policy that allows access from the EC2 instances that are in the private subnets.
Implement an interface VPC endpoint for Amazon SQS. Configure the endpoint to use the public subnets. Attach an Amazon SQS access policy to the interface VPC endpoint that allows requests from only a specified VPC endpoint.
Implement a gateway endpoint for Amazon SQS. Add a NAT gateway to the private subnets. Attach an IAM role to the EC2 instances that allows access to the SQS queue.
Explanations:
Implementing an interface VPC endpoint for Amazon SQS in private subnets allows EC2 instances in private subnets to connect securely to the SQS queue without exposing the traffic to the public internet. The security group ensures that only the allowed EC2 instances can communicate with the SQS endpoint.
Using a public subnet for the interface VPC endpoint contradicts the requirement for a secure connection. EC2 instances in private subnets should not route traffic through public subnets, exposing them to potential security risks.
Similar to option B, configuring the interface VPC endpoint in public subnets does not adhere to best practices for security. Additionally, attaching an SQS access policy to the interface endpoint does not mitigate the risk of exposing private resources to the public internet.
A gateway endpoint for Amazon SQS is not available; SQS requires an interface endpoint. Additionally, using a NAT gateway adds unnecessary complexity and potential exposure, as it would route traffic through the public internet. The IAM role is necessary but not sufficient by itself for secure access from private subnets.
From my point of view, the answer is:
Implement an interface VPC endpoint for Amazon SQS. Configure the endpoint to use the private subnets. Add to the endpoint a security group that has an inbound access rule that allows traffic from the EC2 instances that are in the private subnets.