Implementation summary

In Amazon EFS, a file system is the primary resource. Each file system has properties such as ID, creation token, creation time, file system size in bytes, number of mount targets created for the file system, and the file system lifecycle policies.

Amazon EFS also supports other resources to configure the primary resource. These include mount targets and access points:

• Mount target – To access your file system, you must create mount targets in your VPC. Each mount target has the following properties: the mount target ID, the subnet ID in which it is created, the file system ID for which it is created, an IP address at which the file system may be mounted, VPC security groups, and the mount target state. You can use the IP address or the DNS name in your mount command.

  Each file system has a DNS name of the following form.

  file-system-id.efs.aws-region.amazonaws.com 

  You can specify this DNS name in your mount command to mount the Amazon EFS file system. Suppose you create an efs-mount-point subdirectory off of your home directory on your EC2 instance or on-premises server. Then, you can use the mount command to mount the file system. For example, on an Amazon Linux AMI, you can use the following mount command.

  $ sudo mount -t nfs -o nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport file-system-DNS-name:/ ~/efs-mount-point 

  For more information, see Managing mount targets.

• Access Points – An access point applies an operating system user, group, and file system path to any file system request made using the access point. The access point's operating system user and group override any identity information provided by the NFS client. The file system path is exposed to the client as the access point's root directory. This ensures that each application always uses the correct operating system identity and the correct directory when accessing shared file-based datasets. Applications using the access point can only access data in its own directory and below. For more information, see Working with Amazon EFS access points.

Mount targets and tags are subresources that are associated with a file system. You can only create them within the context of an existing file system.

Amazon EFS provides API operations for you to create and manage these resources. In addition to the create and delete operations for each resource, Amazon EFS supports a describe operation that enables you to retrieve resource information. You have the following options for creating and managing these resources:

• Use the Amazon EFS console – For an example, see Getting started.

• Use the Amazon EFS command line interface (CLI) – For an example, see Tutorial: Create an EFS file system and mount it on an EC2 instance using the AWS CLI.

• You can also manage these resources programmatically as follows:

  • Use the AWS SDKs – The AWS SDKs simplify your programming tasks by wrapping the underlying Amazon EFS API. The SDK clients also authenticate your requests by using access keys that you provide. For more information, see Sample Code and Libraries.

  • Call the Amazon EFS API directly from your application – If you cannot use the SDKs for some reason, you can make the Amazon EFS API calls directly from your application. However, you need to write the necessary code to authenticate your requests if you use this option. For more information about the Amazon EFS API, see Amazon EFS API.