A big data analytics cluster will run on many Linux Amazon EC2 instances across multiple Availability Zones. Every node must have read/write access to shared underlying file storage. The file system must be POSIX-compatible, highly available, resilient, and support very high throughput. Which storage solution satisfies these requirements?

Amazon EFS is the correct choice because it provides a scalable, highly available, and POSIX-compliant file system that can be mounted across multiple EC2 instances in different Availability Zones, meeting the shared read/write access and resiliency requirements. The Max I/O performance mode is specifically designed for applications requiring very high throughput and I/O operations, such as big data analytics clusters. AWS Storage Gateway file gateway backed by S3 would introduce latency and may not meet the very high throughput requirements for real-time analytics. Amazon EBS volumes cannot be simultaneously attached to multiple EC2 instances, making them unsuitable for shared file storage across a cluster. While Amazon EFS General Purpose mode is suitable for many workloads, Max I/O mode is better optimized for the extremely high throughput demands of big data analytics described.