Prerequisites for using the EFS mount helper - Amazon Elastic File System

Prerequisites for using the EFS mount helper

You can mount an Amazon EFS file system on an Amazon EC2 instance using the Amazon EFS mount helper. To use the mount helper, you need the following:

  • File system ID of the file system to mount - The EFS mount helper resolves the file system ID to the local IP address of the mount target elastic network interface (ENI) without calling external resources.

  • An Amazon EFS mount target – You create mount targets in your virtual private cloud (VPC). If you create your file system in the console using the service recommended settings, a mount target is created in each Availability Zone in the AWS Region that the file system is in. For instructions to create mount targets, see Managing mount targets.

    Note

    We recommend that you wait 60 seconds after the newly created mount target's lifecycle state is available before mounting the file system via DNS. This wait lets the DNS records propagate fully in the AWS Region where the file system resides.

    If you use a mount target in an Availability Zone different from that of your EC2 instance, you incur standard EC2 charges for data sent across Availability Zones. You also might see increased latencies for file system operations.

  • For mounting One Zone file systems from a different Availability Zone:

    • The name of the file system's Availability Zone – If you are mounting an EFS One Zone file system that is located in a different Availability Zone than the EC2 instance.

    • Mount target DNS name – Alternatively, you can specify the mount target's DNS name instead of the Availability Zone.

  • An Amazon EC2 instance running one of the supported Linux or macOS distributions – The supported distributions for mounting your file system with the mount helper are the following:

    • Amazon Linux 2

    • Amazon Linux 2023

    • Amazon Linux 2017.09 and newer

    • macOS Big Sur

    • Red Hat Enterprise Linux (and derivatives such as CentOS) version 7 and newer

    • Ubuntu 16.04 LTS and newer

    Note

    EC2 Mac instances running macOS Big Sur support NFS 4.0 only.

  • The Amazon EFS mount helper is installed on the EC2 instance – The mount helper is a tool in the amazon-efs-utils package of utilities. For information about installing amazon-efs-utils, see Automatically installing the EFS client and Manually installing amazon-efs-utils.

  • The EC2 instance is in a VPC – The connecting EC2 instance must be in a virtual private cloud (VPC) based on the Amazon VPC service. It also must be configured to use the DNS server provided by AWS. For information about the Amazon DNS server, see DHCP Options Sets in the Amazon VPC User Guide.

  • VPC has DNS hostnames enabled – The VPC of the connecting EC2 instance must have DNS hostnames enabled. For more information, see Viewing DNS Hostnames for Your EC2 Instance in the Amazon VPC User Guide.

  • For EC2 instances and file systems in different AWS Regions – If the EC2 instance and the file system you are mounting are located in different AWS Regions, you will need to edit the region property in the efs-utils.conf file. For more information, see Mounting EFS file systems from a different AWS Region.