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FTP Server using ProFTPD ​

Set up an FTP server on Virtual Machine PC1 using ProFTPD, allowing clients to upload and download files via FTP.

Install and Configure FTP Server ​

1. Update Package Repository and Install ProFTPD ​

bash
sudo apt-get update

sudo apt-get install proftpd
  • During installation, select "standalone" mode using the arrow keys and press Enter.

2. Configure ProFTPD Settings ​

Edit the main configuration file by opening in nano:

bash
sudo nano /etc/proftpd/proftpd.conf

Make the following changes and save the file:

  1. Disable IPv6:
apache
UseIPv6 off
  1. Set a custom server name:
apache
ServerName "CNLAB.com"
  1. Restrict FTP users to a specific directory (absolute path):

Replace /absolute/path/to/ftp-folder with the actual path of the folder the users should be locked into.

apache
DefaultRoot /absolute/path/to/ftp-folder
  1. Only allow users with valid shells to log in:
apache
RequireValidShell on
  1. Uncomment authentication module line to use Standard Unix authentication :
apache
AuthOrder mod_auth_unix.c

Save and exit:
Press Ctrl + O → Enter → Ctrl + X

3. Add /bin/false to Valid Shells ​

This step ensures that users with /bin/false as their shell can still authenticate for FTP.

bash
sudo nano /etc/shells

Add this line at the end:

/bin/false

Or in a single command:

bash
echo "/bin/false" | sudo tee -a /etc/shells

NOTE

ProFTPD checks if a user has a valid shell (if RequireValidShell on is enabled). Since /bin/false is not considered a "login shell," we must add it to /etc/shells.

4. Create FTP User ​

Create a user with restricted shell access and assign a home directory:

bash
sudo useradd -d /var/www/ -s /bin/false ftpuser

sudo passwd ftpuser

When prompted, enter and confirm a password (e.g., myftp123).

  • -d /var/www/ sets the FTP home directory.

  • -s /bin/false prevents shell login (good for FTP-only users).

5. Create FTP Directory and Set Ownership ​

Ensure the user's home directory exists and has correct permissions:

bash
sudo mkdir -p /var/www/
sudo chown ftpuser:ftpuser /var/www/
sudo chmod 755 /var/www/

chmod 755 allows read & execute access to others so FTP commands work.

6. Allow FTP Through the Firewall (If UFW Is Enabled) ​

If the firewall is active, allow FTP traffic:

bash
sudo ufw allow 21/tcp
sudo ufw reload

7. Restart ProFTPD Service ​

Apply the configuration changes:

bash
sudo systemctl restart proftpd

Check the status:

bash
systemctl status proftpd

8. Test FTP Connection from Client PC (PC2 or PC3) ​

On another PC in the same network:

bash
ftp 172.20.10.X

Replace X with PC1’s actual IP address.
Log in using:

  • Username: ftpuser
  • Password: myftp123 (or your chosen password)

9. Test File Upload/Download ​

Inside the FTP session:

bash
ftp> put Hello.txt      # Upload a file
ftp> get Hello.txt      # Download a file
ftp> ls                 # List directory contents
ftp> quit               # Exit FTP session

10. Fixing Common Errors (Permission Denied) ​

If you see:

550 Hello.txt: Permission denied

Run:

bash
sudo chown ftpuser:ftpuser /var/www/
sudo chmod 755 /var/www/
sudo systemctl restart proftpd

Final Verification ​

  • FTP login should succeed using ftpuser.

  • Uploads (put) and downloads (get) should complete without errors.

  • Directory listing (ls) should show files in /var/www/.