Amazon Elastic File System
User Guide

Amazon EFS File Sync

Using Amazon EFS File Sync, you can easily and efficiently sync files from an existing source file system into a destination Amazon EFS file system. The source file system can be on-premises or in the cloud. With EFS File Sync, you can migrate file-based applications to Amazon EC2 and sync existing datasets into Amazon EFS. EFS File Sync copies your file data, and also file system metadata such as ownership, timestamps, and access permissions.

Requirements for EFS File Sync

Unless otherwise noted, the following are required for creating Amazon EFS File Sync.

Hardware Requirements

When deploying Amazon EFS File Sync on-premises, you must make sure that the underlying hardware on which you are deploying the file sync VM can dedicate the following minimum resources:

  • Four virtual processors assigned to the VM.

  • 32 GB of RAM assigned to the VM

  • 80 GB of disk space for installation of VM image and system data

When deploying Amazon EFS File Sync on Amazon EC2, the instance size must be at least xlarge for your Amazon EFS File Sync to function. We recommend using one of the Memory optimized r4.xlarge instance types.

Supported Hypervisors and Host Requirements

You can choose to run EFS File Sync either on-premises as a virtual machine (VM), or in AWS as an Amazon Elastic Compute Cloud (Amazon EC2) instance.

EFS File Sync supports the following hypervisor versions and hosts:

  • VMware ESXi Hypervisor (version 4.1, 5.0, 5.1, 5.5, 6.0 or 6.5) – A free version of VMware is available on the VMware website. You also need a VMware vSphere client to connect to the host.

  • EC2 instance – EFS File Sync provides an Amazon Machine Image (AMI) that contains the EFS File Sync VM image. We recommend using the Memory optimized r4.xlarge instance types.

Supported NFS Protocols

EFS File Sync supports NFS v3.x, NFS v4.0 and NFS v4.1.

Allowing EFS File Sync Access Through Firewalls and Routers

EFS File Sync requires access to the following endpoints to communicate with AWS. If you use a firewall or router to filter or limit network traffic, you must configure your firewall and router to allow these service endpoints for outbound communication to AWS.

The following endpoints are required by EFS File Sync.

cp-sync.$ activation-sync.$ ec2-* repo.$ packages.$

For information about supported AWS Regions, see Amazon Elastic File System in the AWS General Reference.

The Amazon CloudFront endpoint is required before activation for the sync agent to get the list of available AWS Regions.

Network and Port Requirements

EFS File Sync requires the following ports for its operation.





How Used

EFS File Sync VM



443 (HTTPS)

For communication from EFS File Sync VM to the AWS service endpoint. For information about service endpoints, see Allowing EFS File Sync Access Through Firewalls and Routers.

Your web browser

EFS File Sync VM


80 (HTTP)

By local systems to obtain the sync agent activation key. Port 80 is used only during activation of the EFS File Sync agent.

EFS File Sync VM doesn't require port 80 to be publicly accessible. The required level of access to port 80 depends on your network configuration. If you activate your sync agent from the Amazon EFS Management Console, the host from which you connect to the console must have access to port 80.

EFS File Sync VM

Domain Name Service (DNS) server


53 (DNS)

For communication between EFS File Sync VM and the DNS server.

EFS File Sync VM



22 (Support channel)

Allows AWS Support to access your EFS File Sync to help you with troubleshooting EFS File Sync issues. You don't need this port open for normal operation, but it is required for troubleshooting.

EFS File Sync VM

NTP server


123 (NTP)

By local systems to synchronize VM time to the host time.

EFS File Sync VM

NFS Server


2049 (NFS)

By EFS File Sync VM to mount source NFS filesystem.

Supports NFS v3.x, NFS v4.0 and NFS v4.1.

Following is an illustration of the required ports and lists the ports required by EFS File Sync.

EFS File Sync Architecture

EFS File Sync provides the following benefits:

  • Efficient high-performance parallel data transfer that tolerates unreliable and high-latency networks.

  • Encryption of data transferred from your IT environment to AWS.

  • Data transfer rate up to five times faster than standard Linux copy tools.

The following diagram shows a high-level view of the EFS File Sync architecture.

To sync files from an existing file system to Amazon EFS

  1. Open the Amazon EFS Management Console at

  2. Download and deploy a sync agent. For on-premises deployment, the sync agent is provided as a virtual machine (VM) image for VMware ESXi. For an AWS Cloud deployment, you can create an Amazon EC2 instance from the community Amazon Machine Image (AMI).

  3. Create a sync task and configure your source and destination file systems.

  4. Start your sync task to begin syncing files from the source file system to the Amazon EFS file system.

  5. Monitor your sync task on the Amazon EFS console or from Amazon CloudWatch. For more information, see Monitoring EFS File Sync with Amazon CloudWatch.

For more details on the EFS File Sync process, see the following: