Best practices for using the Snowball Edge device - AWS Snowball Edge Developer Guide

Best practices for using the Snowball Edge device

To help get the maximum benefit and satisfaction with your AWS Snowball Edge device, we recommend that you follow these best practices.


The following are recommendations and best practices for maintaining security while working with an AWS Snowball Edge device.

General Security
  • If you notice anything that looks suspicious about the AWS Snowball Edge device, don't connect it to your internal network. Instead, contact AWS Support, and a new AWS Snowball Edge device will be shipped to you.

  • We recommend that you don't save a copy of the unlock code in the same location on the workstation as the manifest for that job. Saving these in different locations helps prevent unauthorized parties from gaining access to the AWS Snowball Edge device. For example, you can save a copy of the manifest to your local server, and email the code to a user that unlocks the device. This approach limits access to the AWS Snowball Edge device to individuals who have access to files saved on the server and the user's email address.

  • The credentials displayed, when you run the Snowball Edge client commands list-access-keys and get-secret-access-key, are a pair of access keys used to access your device.

    These keys are only associated with the job and the local resources on the device. They don't map to your AWS account or any other AWS account. If you try to use these keys to access services and resources in the AWS Cloud, they will fail because they only work for the local resources associated with your job.

  • If you feel your credentials are lost or have been compromised, request a new manifest file and unlock code by following the process to update the device's SSL certificate. See Updating the SSL certificate.

For information about how to use AWS Identity and Access Management (IAM) policies to control access, see AWS-Managed (Predefined) Policies for AWS Snowball Edge.

Network Security
  • We recommend that you only use one method at a time for reading and writing data to a local bucket on an AWS Snowball Edge device. Using both the file interface and the Amazon S3 adapter on the same Amazon S3 bucket at the same time can result in read/write conflicts.

  • To prevent corrupting your data, don't disconnect the AWS Snowball Edge device or change its network settings while transferring data.

  • Files that are being written to on the device should be in a static state. Files that are modified while they are being written to can result in read/write conflicts.

  • For more information about improving performance of your AWS Snowball Edge device, see Performance.

Resource Management

Consider the following best practices for managing jobs and resources on your AWS Snowball Edge device.

  • The 10 free days for performing your on-premises data transfer start the day after the AWS Snowball Edge device arrives at your data center. This applies only to Snowball Edge device types.

  • The Job created status is the only status in which you can cancel a job. When a job changes to a different status, you can't cancel the job. This applies to clusters.

  • For import jobs, don't delete your local copies of the transferred data until the import into Amazon S3 is successful. As part of your process, be sure to verify the results of the data transfer.



The data transfer performance you experience will vary based on the network environment, operating systems, copy method, protocol, source data read performance, and dataset characteristics such as file size. To determine the accurate data transfer rates and data transfer times, we recommend you to measure performance through proof-of-concept testing in your environment.

Following, you can find recommendations and information about AWS Snowball Edge device performance. This section describes performance in general terms, because on-premises environments have a different way of doing things—different network technologies, different hardware, different operating systems, different procedures, and so on.

The following table outlines how your network's transfer rate impacts how long it takes to fill a Snowball Edge device with data. Transferring smaller files reduces your transfer speed due to increased overhead. If you have many small files, we recommend that you zip them up into larger archives before transferring them onto a Snowball Edge device.

Rate (MB/s) 82 TB transfer time
800 1.22 days
450 2.11 days
400 2.37 days
300 3.16 days
277 3.42 days
200 4.75 days
100 9.49 days
60 15.53 days
30 31.06 days
10 85.42 days

To provide meaningful guidance about performance, the following sections describe how to determine when to use the AWS Snowball Edge device and how to get the most out of the service.

Performance Recommendations

The following practices are highly recommended, because they have the largest impact on improving the performance of your data transfer:

  • We recommend that you have no more than 500,000 files or directories within each directory.

  • We recommend that all files transferred to a Snowball Edge device be no smaller than 1 MB in size.

  • If you have many files smaller than 1 MB in size, we recommend that you zip them up into larger archives before transferring them onto a Snowball Edge device.

Speeding Up Data Transfer

One of the best ways that you can improve the performance of an AWS Snowball Edge device is to speed up the transfer of data going to and from a device. In general, you can improve the transfer speed from your data source to the device in the following ways. This following list is ordered from largest to smallest positive impact on performance:

  1. Perform multiple write operations at one time – To do this, run each command from multiple terminal windows on a computer with a network connection to a single AWS Snowball Edge device.

  2. Transfer small files in batches – Each copy operation has some overhead because of encryption. To speed up the process, batch files together in a single archive. When you batch files together, they can be auto-extracted when they are imported into Amazon S3. For more information, see Batching small files.

  3. Don't perform other operations on files during transfer – Renaming files during transfer, changing their metadata, or writing data to the files during a copy operation has a negative impact on transfer performance. We recommend that your files remain in a static state while you transfer them.

  4. Reduce local network use – Your AWS Snowball Edge device communicates across your local network. So you can improve data transfer speeds by reducing other local network traffic between the AWS Snowball Edge device, the switch it's connected to, and the computer that hosts your data source.

  5. Eliminate unnecessary hops – We recommend that you set up your AWS Snowball Edge device, your data source, and the computer running the terminal connection between them so that they're the only machines communicating across a single switch. Doing so can improve data transfer speeds.