What is Elastic File System?

• It is a “shared” managed Network File System (NFS) that can be mounted on hundreds of EC2 instances.
• EFS works with Linux EC2 instances in a multi-AZ.

Features

• High Available
• Scalable
• EXPENSIVE ($$$)
• Pay Per Use
• No Capacity Planning

Difference Between EBS & EFS

EBS data is not accessible across AZs and Regions(directly, without snapshoting) while EFS can connect to any EC2 instance across AZs & regions for the same.

- Storage class that is cost-optimized for files not accessed everyday. - Upto 92% lower cost as compared to EFS (standard). - EFS will automatically move your files to EFS-IA based on the last time they were accessed. - We can enable EFS-IA with a lifecycle policy - E.G. Move files not accessed for 60 days to EFS-IA - Transparent to the application accessing EFS (i.e. the app will not need to know if the data is stored in EFS or EFS-IA)

Elastic File System - Shared Responsiblity

Responsiblity of AWS	Responsiblity of Customer
Infrastructure	Setting up Backup/Snapshot procedures
Replication od fata for EBS volume & EFS drives	Responsiblity of any data on the drives
Replacing faulty hardware	Understanding the risk of using EC2 Instance Store
Ensuring AWS Employee cannot access client Data