Which solutions meet these requirements?
(Choose two.)
Use AWS Storage Gateway Volume Gateway Internet Small Computer Systems Interface (iSCSI) block storage that is mounted to the individual EC2 instances.
Create an Amazon Elastic File System (Amazon EFS) file system. Mount the EFS file system on the individual EC2 instances.
Create a shared Amazon Elastic Block Store (Amazon EBS) volume. Mount the EBS volume on the individual EC2 instances.
Use AWS DataSync to perform continuous synchronization of data between EC2 hosts in the Auto Scaling group.
Create an Amazon S3 bucket to store the web content. Set the metadata for the Cache-Control header to no-cache. Use Amazon CloudFront to deliver the content.
Explanations:
Amazon EFS provides a scalable and fully managed NFS file system that can be mounted by multiple EC2 instances across different Availability Zones, providing strong consistency and shared access to content. This satisfies the requirement for strong consistency and frequent content updates.
Amazon S3 with CloudFront can provide strong consistency when writing to S3. By setting the Cache-Control header to no-cache, CloudFront will fetch the updated content immediately after a change in S3, ensuring that the new content is served as soon as changes occur.
AWS Storage Gateway Volume Gateway is primarily used for hybrid cloud storage solutions involving on-premises systems, not for EC2 instances. It also does not provide the same level of consistency or scalability as other solutions for web applications.
Amazon EBS volumes can only be attached to a single EC2 instance at a time. This would limit scalability and does not provide shared access or strong consistency across multiple EC2 instances in an Auto Scaling group.
AWS DataSync is designed for moving large amounts of data between storage systems, not for real-time content synchronization across EC2 instances. It would not meet the requirement for frequent updates and strong consistency in a web application environment.