To open port 21 on firewall is an easy task.
That is the one that typically connects to well known FTP port 21.Īny data transfer, such as directory listing, upload and download happen on secondary connection called data channel. The root cause for this challenge lies in the FTP protocol architecture.Įach FTP client requires 2 connections to be maintained between client and server.įTP commands are transferred over connection called control channel. It is often a challenge to setup firewall rules for FTP server to work correctly. This post does NOT address IP address translation related issues and other issues that apply when there is an external firewall (such as ISA server) between client and server.
The goal of this post if to provide instructions on how to setup local Windows Firewall to enable access to FTP over non-secure or secure connections. This post is the first one from the mini-series on firewall configuration for FTP7 (full product name: Microsoft FTP Publishing Service for IIS 7.0).
