A Guide to Setup an SFTP Server on Linux

Introduction

Some of the benefits of SFTP are:

• Secure File Transfer – SFTP is primarily used for securely transferring files between systems over an insecure network, such as the internet. It ensures that data remains confidential and protected from unauthorized access during transit.
• Remote Server Administration – SFTP is commonly used by system administrators to remotely manage servers. They can securely upload, download, and modify files on the server, perform backups, update configurations, and execute administrative tasks.
• Website Maintenance – SFTP is often employed by web developers and designers to update and maintain websites hosted on remote servers. It allows them to upload new files, modify existing ones, and manage the website’s directory structure securely.
• Automated File Transfers – SFTP can be integrated into automated workflows and scripts, allowing for the scheduled or event-driven transfer of files between systems. This is useful for tasks like data backups, synchronizing files between servers, and distributing files to multiple locations.
• Secure Data Exchange – Organizations that need to exchange sensitive data with external partners, clients, or suppliers can utilize SFTP to ensure the secure transfer of files. SFTP’s encryption and authentication mechanisms provide a higher level of security compared to traditional FTP.
• Cloud Storage Integration – Many cloud storage providers support SFTP as a method for securely accessing and transferring files to and from cloud storage. This enables users to interact with their cloud-based files using SFTP clients, providing an additional layer of security.

Step-by-Step Guide

Step 1: Set up an SFTP directory on a Linux server

In the below scenario, we are using Ubuntu 20.4 server hosted on Azure.

We will create a directory named ‘data’ under / directory with full owner permissions, group no permissions, and others only execute permission.

Step 2: Create an SFTP group and user

Now we will create a group named ‘sftp_users’ and add the user ‘YOURUSERNAME’ to group ‘sftp_users’ only for sftp.

Run the below commands for the same

Step 3: Set up a new user SFTP directory

Now, we will create a directory ‘YOURUSERNAME/upload’ under ‘/data’ directory with user  ‘root’ as the owner and ‘sftp_users’ group as the group for directory /data/YOURUSERNAME.

user ‘YOURUSERNAME’ as owner and ‘sftp_users’ group as the group for directory /data/YOURUSERNAME/upload

Run the below commands for the same.

Step 4: Configure sshd using the below command

Step 5: Save the File and run the below command to restart the sshd service

Step 6: Logging in

From a different machine on your network that has SSH installed, open a new terminal window and run the below command:

Step 7: Upload a file

Now, let’s upload a ‘test’ file to sftp server using PUT command.

Verify our upload by browsing to the sftp directory, which we created in Step 3

Conclusion

This blog shows how to set up an SFTP server and transfer files securely from a local machine to a remote server using the SFTP protocol.

Other alternative file transfer clients using SSH besides CLI are SCP, FileZilla, etc.

About CloudThat