Amazon Elastic File System Concepts
Internal
Overview
Amazon Elastic File System (EFS) provides a scalable filesystem for Linux-based workloads for use with AWS cloud services and on-premises resources. More details about the specifics of the filesystem are available in the EFS File System section below.
EFS is built to scale on demand to petabytes without disrupting applications, growing and shrinking automatically as files are added and removed. It is designed to provide massively parallel shared access to thousands of Amazon EC2 instances, enabling applications to achieve high levels of aggregate throughput and IOPS with consistent low latencies. Amazon EFS is a fully managed service that requires no changes to existing applications and tools, providing access through a standard file system interface. Amazon EFS is a regional service storing data within and across multiple Availability Zones. The filesystems can be accessed across Availability Zones and regions via AWS Direct Connect or AWS VPN.
Amazon EFS is well suited to support a broad spectrum of use cases from highly parallelized, scale-out workloads that require the highest possible throughput to single-threaded, latency-sensitive workloads. Use cases such as lift-and-shift enterprise applications, big data analytics, web serving and content management, application development and testing, media and entertainment workflows, database backups, and container storage.
EFS and EC2
EFS File System
The EFS file system materializes as a POSIX-compliant file system mounted in an EC2 instance, a Docker container or a EKS pod. Most common use case is to mount EFS file systems on instances running in the AWS Cloud, but it is also possible to mount these file systems on instances running in on-premises data center, with AWS Direct Connect or AWS VPN.
The persistent storage backing up the EFS file system is managed by the AWS infrastructure and it is not accessible directly. However, an EFS file system can be accessed from a VPC via a mount target. The underlying protocol used to mount EFS file systems is NFS 4.0 and 4.1, so the appropriate NFS client must be available in the environment attempting to mount the file system.
Mount Target
A mount target can be logically thought of as an NFS server with a fixed IP address that exists in a particular subnet in a VPC. The mount target provides the IP address for the NFSv4 endpoint at which the EFS file system can be mounted.
The mount target IP address is associated with a DNS name.
In case of multiple subnets in the same Availability Zone, a mount target must be created for each subnet, and each EC2 instances in the subnet can share the mount target.
An EFS file system can only have mount targets in one VPC at a time.
Mount targets are designed to be highly available.
Access Point
Data Sharing and Consistency
An EFS file system can be accessed concurrently from multiple NFS clients, deployed within multiple Availability Zones within the same AWS Region.
EFS Operations
- Create a file system