What should a solutions architect do to improve the reliability and scalability of the SFTP solution?
Move the EC2 instance into an Auto Scaling group. Place the EC2 instance behind an Application Load Balancer (ALB). Update the DNS record sftp.example.com in Route 53 to point to the ALB.
Migrate the SFTP server to AWS Transfer for SFTP. Update the DNS record sftp.example.com in Route 53 to point to the server endpoint hostname.
Migrate the SFTP server to a file gateway in AWS Storage Gateway. Update the DNS record sftp.example.com in Route 53 to point to the file gateway endpoint.
Place the EC2 instance behind a Network Load Balancer (NLB). Update the DNS record sftp.example.com in Route 53 to point to the NLB.
Explanations:
While placing the EC2 instance in an Auto Scaling group and behind an Application Load Balancer (ALB) could improve scalability, ALBs are not suitable for SFTP, which requires TCP connections. Additionally, using an EC2 instance means managing the server, which may not provide the best reliability.
Migrating to AWS Transfer for SFTP provides a fully managed service that handles SFTP without the need for server management. It offers scalability and high availability, while automatically integrating with Amazon S3 for storage, improving reliability and ease of use.
Migrating the SFTP server to a file gateway in AWS Storage Gateway is not a valid solution for SFTP as the file gateway is designed for file storage access over protocols like NFS and SMB, not for SFTP. This option does not meet the requirement of providing a reliable SFTP service.
Although placing the EC2 instance behind a Network Load Balancer (NLB) would help distribute traffic and improve availability, it does not solve the underlying management and scalability issues of maintaining an EC2-based SFTP server. The solution would still require management of the instance and its scaling.