Amazon Elastic File System (Amazon EFS) provides a simple, scalable, fully managed elastic NFS (Network File System) that can be mounted on multiple EC2.
It supports the Network File System version 4 (NFSv4.1 and NFSv4.0) protocol.
Multiple Amazon EC2 instances can access an Amazon EFS file system at the same time, providing a common data source for workloads and applications
It is compatible with only Linux based EMI. For Windows you need to use FSx service
The service is designed to be highly scalable, highly available, and highly durable.
Amazon EFS file systems store data and metadata across multiple Availability Zones in an AWS Region.
It also supports authentication, authorization, and encryption capabilities to help you meet your security and compliance requirements.
You need to pay 3 times more than GP2 storage (3x GP2) – Pay per use.
You can backup EFS-to-EFS
You can also synchronize on-premise file server data to EFS.
You need to attach a security group to EFS volume network drive in order to allow access over the network
Elastic File System
Difference between EBS and EFS
EBS volumes can be attached to only one instance at a time. EFS is used as a shared drive and can be accessible on multiple instances
Migrating an EBS volume across AZ means first backing it up (snapshot), then recreating it in the other AZ.
