Build a Simple FTP Server in 9 Python Lines with pyftpdlib

Objective

Demonstrate how to create a functional FTP server using only nine lines of Python code.

Prerequisites

Install the third‑party library pyftpdlib with pip3 install pyftpdlib.

Implementation

Below is the minimal script (comments omitted for brevity):

from pyftpdlib.authorizers import DummyAuthorizer
from pyftpdlib.handlers import FTPHandler
from pyftpdlib.servers import FTPServer

authorizer = DummyAuthorizer()
authorizer.add_user("ljds", "ljds", ".", perm="elradfmw")
handler = FTPHandler()
handler.authorizer = authorizer

server = FTPServer(("192.168.1.102", 21), handler)
server.serve_forever()

The authorizer.add_user line creates an FTP login with username ljds , password ljds , the current directory as the root ("."), and full permissions ( elradfmw).

The FTPServer line binds the server to the LAN IP address 192.168.1.102 on the default FTP port 21.

Running the Server

Execute the script, then open a browser or FTP client and navigate to ftp://192.168.1.102. After entering the credentials, the FTP directory listing is displayed.

Common Issue

The author experienced that using the loopback address 127.0.0.1 works only on the local machine; external access requires the actual LAN IP (e.g., 192.168.1.102), which resolves the connectivity problem.