AWS Solutions Architect Associate Practice Test: Exam Prep & Study Guide

Running a database on an EC2 instance requires a storage solution that provides low-latency access, consistent performance, and the capability to perform frequent I/O operations. EBS (Elastic Block Store) is specifically designed for this kind of use case. It offers block-level storage that can be attached to an EC2 instance, making it ideal for databases where you need to read and write data quickly.

EBS volumes are persistent, which means that the data stored on them is retained even if the EC2 instance is stopped or terminated. Additionally, EBS supports features like snapshots for data backup and restoration, which is crucial for maintaining database integrity and availability.

In comparison, while RDS is a managed database service, it is not the storage option you would directly choose for running a database on EC2 since RDS itself abstracts the underlying storage. S3 is designed for object storage, which is better suited for storing unstructured data rather than for databases requiring fast access. Glacier is a long-term archival storage service, making it unsuitable for the needs of a running database that requires quick access to its data.

These characteristics make EBS the most recommended storage option for databases running on EC2 instances, as it meets the performance and reliability requirements for such workloads