In this guide, we will show you how to setup an SFTP server using VSFTPD on Ubuntu 20.04 Focal Fossa. If you haven’t already, check out our tutorial on How to setup FTP server on Ubuntu 20.04 Focal Fossa with VSFTPD, as this article on SFTP assumes that you’ve applied the configuration covered in the FTP guide.
FTP is a great protocol for accessing and transferring files, but it has the shortcoming of being a clear text protocol. In other words, it’s not secure to use over an internet connection, since your credentials and data are transmitted without encryption. The ‘S’ in SFTP stands for ‘Secure’ and tunnels the FTP protocol through SSH, providing the encryption needed to establish a secure connection.
In this tutorial you will learn:
- How to install and configure SSH daemon
- How to setup an SFTP user account and group
- How to connect to SFTP server via command line
- How to connect to SFTP server via command line
|Category||Requirements, Conventions or Software Version Used|
|System||Installed or upgraded Ubuntu 20.04 Focal Fossa|
|Software||VSFTPD, SSH daemon|
# – requires given linux commands to be executed with root privileges either directly as a root user or by use of
$ – requires given linux commands to be executed as a regular non-privileged user
Configure SSH daemon
- SFTP requires SSH, so if SSH server is not already installed on your system, install it with the following command:
$ sudo apt install ssh
- Once SSH is installed, we need to make some changes to the SSHD configuration file. Use nano or your favorite text editor to open it:
$ sudo nano /etc/ssh/sshd_config
- Scroll to the bottom of the file and add the following 5 lines at the very end:
Match group sftp ChrootDirectory /home X11Forwarding no AllowTcpForwarding no ForceCommand internal-sftp
The lines above will allow users in the
sftpgroup to access their home directories via SFTP, but denies them normal SSH access, so they can never access a shell. After pasting those lines, save and close the configuration file.
- Restart the SSH service for these new changes to take effect:
$ sudo systemctl restart ssh
Create SFTP user account
Now we need to create user accounts for anyone that we wish to grant SFTP access to.
- Create a new user group called
sftp. All of our SFTP users will need to belong to this group.
$ sudo addgroup sftp Adding group `sftp' (GID 1002) ... Done.
- Next, create a new user. We’ll simply call ours
sftpuserin this example. Also be sure to add this user to the
$ sudo useradd -m sftpuser -g sftp
- Set a password for the newly created
$ sudo passwd sftpuser New password: Retype new password: passwd: password updated successfully
- Lastly, let’s grant full access to the user on their own home directory, but deny access to the directory for all other users on the system:
$ sudo chmod 700 /home/sftpuser/
Our SFTP configuration is complete; now we can login to make sure everything is working properly.
Login to SFTP using command line
You can login via SFTP with either the hostname or IP address of your system. To test from the same system as the one you just configured SFTP on, connecting to the loopback address
127.0.0.1 will work just fine.
- Open a terminal and login using the
$ sftp email@example.com The authenticity of host '127.0.0.1 (127.0.0.1)' can't be established. ECDSA key fingerprint is SHA256:9HZflwSB64J+SELGLczOuv3f06gT/3ZaZAOezVZn2XQ. Are you sure you want to continue connecting (yes/no/[fingerprint])? yes Warning: Permanently added '127.0.0.1' (ECDSA) to the list of known hosts. firstname.lastname@example.org's password: Connected to 127.0.0.1. sftp>
- Navigate to the user’s home directory, since that’s the only place it has permissions. In here, try making a new directory to confirm that everything is working as intended:
sftp> cd sftpuser sftp> mkdir sftp-test sftp> ls sftp-test sftp>
Login to SFTP using GUI
If you prefer to use a GUI application to connect to your SFTP server, there are lots of options available. You can use your preferred SFTP client or the one built into Ubuntu by default – the Nautilus file manager.
- Open Nautilus file manager from within the Applications menu.
- Click on “Other Locations” and enter
sftp://127.0.0.1in the “Connect to server” box at the bottom of the window and click connect.
- Enter the SFTP account’s credentials that we setup earlier and click connect.
- Upon a successful connection, you’ll be able to open your home directory and see the test directory you created earlier.
In the FTP Server article, we saw how to use VSFTPD to create an FTP server on Ubuntu 20.04 Focal Fossa. We also covered how to use the command line and Ubuntu GUI to connect to the FTP server.
In this article, we saw how to secure the FTP protocol by setting up SFTP on our system. By following the instructions in this guide, computers on your local network or across the internet can securely access your system to store and retrieve files, either via the command line or their preferred SFTP client.