Elastic File System (EFS) is a scalable managed service that implements the Network File System (NFSv4).
- File systems can be mounted on multiple Linux instances at the same time. -> shared media, home folder, shared documents.
- It can be accessed in the VPC, across the VPC, and even from outside of VPC through Direct Connect.
- EFS is built to scale while maintaining low latency and high throughput. It can support thousands of current NFS connections.
- EFS is a regional service that stores data across multiple AZs for high availability and durability.
- EFS supports Read after Write consistency.
How to configure EFS
- Select VPC -> Create mount targets in AZs with a security group
- Security Group is used to control access NFS mount targets.
- Mount targets sit inside a subnet.
Performance Mode
- General Purpose: a default and fits for most of cases
- Max I/O: when a large number of instances need to access a file system
Throughput Mode
- Bursting throughput: linked to the size of data stored within the EFS.
- Provisioned throughput: independent of size
Storage Classes
- EFS supports 2 storage Classes: Standard and Infrequent Access (IA)
- Lifecycle move files between classes.
Moving Files to EFS IA
- Create a file system
- Choose Lifecycle Management file access policy (7, 14, 30, 60, or 90 days)
- Files not accessed according to the age-off policy are moved to EFS IA
