Guide to FTP/SFTP Access to an Amazon S3 Bucket

SFTP is a secure shell protocol used to transfer files and directories between Linux and Windows servers. It is used by developers, website owners, financial services, and healthcare to exchange data between business clients. SFTP uses an SSH protocol for the secure transfer of files over the internet.

AWS Transfer Family is a fully managed AWS service that enables you to transfer files to and from Amazon S3 buckets. AWS Transfer Family uses SSH, SFTP, FTPS, and FTP protocol to transfer files over the internet.

Files.com is an extremely fast, reliable, and enterprise-ready file server solution that allows users to upload and share files. Files are encrypted and designed to work with all protocols. It can be integrated with different cloud providers including, Amazon S3, Dropbox, Google Drive, Microsoft Azure, SFTP, Microsoft One Drive, Sharepoint, Box, and many more to mount and sync files and directories.

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• Compatible with almost all devices and is simple to use.
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• Especially for huge files (up to 5TB), Files.com proves to be highly ingenious.

In this post, you will learn the following:

• Create an Amazon S3 bucket.
• Create an IAM Role for SFTP Users.
• Create SFTP Server on Amazon AWS.
• Access SFTP server from Linux.
• Integrate Files.com with Amazon SFTP Server and mount S3 bucket to Files.com.

Create an Amazon S3 bucket

In this section, we will create a bucket on Amazon S3.

Follow the below steps to create a bucket:

1. log in to the AWS console at https://console.aws.amazon.com/

2. Search for S3 in the search bar. You should see the following screen:

3. Click on S3. You should see the Amazon S3 dashboard on the next screen:

4. Click on the Create bucket button. You should see the next screen:

5. Provide your bucket name, select your AWS region, and click on the Create bucket button. Once the bucket has been created successfully, you should see the next screen:

Create an IAM Role for SFTP Users

Next, you will need to create an IAM role for SFTP users with an updated trust relationship.

Follow the below steps to create an IAM role:

1. Search for IAM in the search bar. You should see the following screen:

2. Click on IAM. You should see the following screen:

3. Click on the Create role button. You should see the following screen:

4. Select EC2 and click on the Next: Permissions. You should see the following screen:

5. Search for AmazonS3FullAccess in the Filter policies search box, select AmazonS3FullAccess policy and click on the Next: Tags button. You should see the following screen:

6. Provide the name and value of your Tag and click on the Next: Review button. You should see the following screen:

7. Provide your Role name, description, and click on the Create role button. Once the Role has been created successfully, you should see the following screen:

8. Next, click on your roles. You should see the following screen:

9. Click on the Trust relationships tab. You should see the following screen:

10. Click on Edit trust relationship. You should see the following screen:

11. Replace the line ec2.amazonaws.com with transfer.amazonaws.com for sftp service to work. Then, click on the Update Trust Policy button on the corner right side.

Create SFTP Server on Amazon AWS

Next, you will need to create an SFTP server on AWS using the AWS Transfer Family service.

Follow the below steps to create an SFTP server.

1. Search for SFTP on the search bar. You should see the following screen:

2. Click on AWS Transfer Family. You should see the AWS Transfer Family dashboard:

3. Click on the Create server button. You will be asked to choose the protocols as shown below:

4. Select SFTP protocol and click on the Next button. You will be asked to select an identity provider as shown below:

5. Select Service Manage and click on the Next button. You will be asked to select an endpoint as shown below:

6. Select endpoint type, hostname, and click on the Next button. You will be asked to choose a domain as shown below:

7. Select Amazon S3 and click on the Next button. You will be asked to configure additional details as shown below:

8. Provide relevant details and click on the Next button. You should see the following screen:

9. Review all the settings and click on the Create server button. Once the SFTP server has been created successfully, you should see the following screen:

10. As you can notice, there are no users created yet, so click on the button Add User for creating users who will be accessing this sftp service. Next, click on your SFTP server. You should see the following screen:

11. Now, click on the Add user button. You should see the user configuration page:

12. Here, provide your desired SFTP username, select the SFTP role we have created earlier, and select the S3 bucket we created earlier. You will also need to provide an SSH public key of the remote machine from where you want to access the SFTP server.

To generate an SSH key on the remote machine, run the following command:

ssh-keygen -P "" -f "sftp-key"

You should see the following output:

Generating public/private rsa key pair.
Your identification has been saved in sftp-key.
Your public key has been saved in sftp-key.pub.
The key fingerprint is:
c6:e0:7b:73:5c:1d:4e:e7:3b:ab:6d:69:f1:c9:91:91 vyom@newpc
The key's randomart image is:
+--[ RSA 2048]----+
| |
| |
| . o o|
| . o + E |
| . S . o +|
| o . . +.|
| . o o .o*|
| . o .*+|
| .+o |
+-----------------+

You can see the generated keys using the following command:

ls -l sftp*

You should see the following output:

-rw------- 1 vyom vyom 1675 Jul 28 16:53 sftp-key
-rw-r--r-- 1 vyom vyom 392 Jul 28 16:53 sftp-key.pub

Now, print the content of the sftp-key.pub public key:

cat sftp-key.pub

You should see the following output:

ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDXeyyWpl5yXA1Zadz3x1Kb6J9XCQXr5d0nLUmOpOhhzdAjlbC3ykx93qu9i0cz3PV07XgcNaJpHm65VdB3nCxrMxYS91qeHm32Cnt3GI4o8TGHyjFBycOh8lo8lVF2OYPelOufEOXW1nZTDpGEW5MOOLM078LcoECskLWTOXyjopGhKqiHu/04cIvjo5YDHUbjoRhEryzDaSWnHe3KCz9q4TtQAAOU3Jc5iZeZH6o7CE3uUlGAppBd6gdvmBnccFBQC36+zmskbYciLDH398XYpg3r9fL4fdJlgjjhCg62m+rMCNtJDApLJdbIN477JloVr4iZcc3ysM16Dl3qTZIJ

Now, copy the above key and paste it into the SFTP server dashboard. Then, click on the Add button. Once the user has been added successfully, you should see the following screen:

Access SFTP server from Linux

At this point, the SFTP server has been installed and configured on Amazon AWS. Now, we will access the SFTP server from the remote Linux machine.

Log in to the remote Linux machine, open the command-line terminal and access the SFTP server using the following command:

sftp -i sftp-key sftpuser@s-71d3de4c8b6045b7b.server.transfer.us-east-2.amazonaws.com

Where:

• sftp: It is a command used to connect remote SFTP server.
• -i sftp-key: A private key is used to connect to an SFTP server without a password.
• sftpuser: It is the name of the SFTP username.
• s-71d3de4c8b6045b7b.server.transfer.us-east-2.amazonaws.com: It is the full URL of your SFTP server.

Once you are connected to the SFTP server, you should see the following output:

The authenticity of host 's-71d3de4c8b6045b7b.server.transfer.us-east-2.amazonaws.com (3.129.55.151)' can't be established.
RSA key fingerprint is ae:2e:cc:31:92:c9:a1:fe:d8:83:c0:08:2e:6b:49:fe.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 's-71d3de4c8b6045b7b.server.transfer.us-east-2.amazonaws.com,3.129.55.151' (RSA) to the list of known hosts.
Connected to s-71d3de4c8b6045b7b.server.transfer.us-east-2.amazonaws.com.
sftp>

Now, create some directories on the SFTP server using the following commands:

sftp> mkdir dir1
sftp> mkdir dir2

Now, upload a file named lets from the local system to the SFTP server:

sftp> put lets

You should see the following output:

Uploading lets to /bucket-1981/sftpuser/lets
lets 100% 29 0.0KB/s 00:00

Now, login to the AWS console and go to the S3 bucket. You should see the following screen:

Click on the sftpuser home directory. You should see your file and guides on the following screen:

Integrate Files.com with Amazon SFTP Server.

This section will show you how to connect the Amazon S3 bucket from Files.com and mount the S3 bucket to Files.com.

Follow the below steps to integrate Files.com with the Amazon SFTP server:

1. log in to Files.com and click on Integrations. You should see the following screen:

2. Click on the Amazon S3. You should see the following screen:

3. Click on Add Amazon S3 as a remote server. You will be asked to provide your Amazon S3 credentials as shown below:

4. Provide a connection name, S3 bucket name, AWS region, AWS access key, AWS secret key and click on the Save button. Once you are connected to AWS S3 successfully, you should see the following screen:

5. Next, click on the Files on the Files.com dashboard. You should see the following screen:

6. Click on the New folder to create a new directory on Files.com. You will be asked to provide the name of the folder as shown below:

7. Provide a folder name and click on the Create button.

8. Next, navigate to your newly created folder and click on the Folder settings. You should see the following screen:

9. Next, click on the Remote server mount. You should see the following screen:

10. Click on Add new remote server mount. You should see the following screen:

11. Select your AWS S3 server, remote folder path, and click on the Save button. Once you are connected, you should see the following screen:

12. Now, click on sftpuser. You should see that all directories and files are mounted on Files.com:

13. Now, click on the New folder to create a new folder on the mount point. You should see the following screen:

14. Provide your folder name and click on the Create button. You should see the following screen:

15. Now, go back to your AWS S3 bucket. You should also see your newly created folder there.

Conclusion

In the above guide, you learned how to create an SFTP server on Amazon S3 and integrate it with Files.com. I would recommend Files.com for secure storage and transfer of your files, especially huge ones. Files.com offers a 7-day free trial of their services.

FTP/SFTP Access to an Amazon S3 Bucket FAQs