Elastic Block Store (EBS) provides block-device storage as volumes to EC2 instances. It behaves similarly to a storage area network (SAN) and offers the lowest-latency access of the various storage services offered. EBS volumes can only be accessed by one instance at a time. The size of a volume must be specified when they are provisioned, and cannot be changed after.
Volumes are hosted on redundant hardware in a specific AZ, but they do not offer redundancy across AZs.
Some recommended use cases for EBS are:
- Instance boot volumes
- Intensive data processing
- Transactional writes
We will cover EBS in more detail in the Chapter 4, Using AWS Compute, as its primary use is as the underlying storage for EC2 instances.
