Which AWS service is considered suitable for providing shared storage for multiple EC2 instances?

The most suitable AWS service for providing shared storage for multiple EC2 instances is Amazon EFS (Elastic File System). Amazon EFS is a managed file storage service that allows you to create file systems that can be mounted concurrently by many EC2 instances across multiple Availability Zones. This capability makes it an ideal solution for applications that require a file system interface and shared access to data.

EFS is designed for use cases that involve shared file storage, such as content management, web serving, and big data applications where multiple instances need simultaneous access to the same files. The service supports standard file system interfaces, allowing you to use it seamlessly with existing applications that rely on file storage.

Amazon S3 is primarily an object storage service intended for storing and retrieving any amount of data. It provides high durability and scalability but does not offer a traditional file system interface suitable for shared access as EFS does.

Amazon Glacier is a low-cost archival storage service designed for long-term data archival and is not intended for shared access or frequently accessed data.

Amazon RDS is a managed relational database service. While it is useful for database operations, it does not provide a shared file system for EC2 instances in the way that EFS does.

Thus, Amazon EFS stands out as