How to Find FTP Sites

Locating FTP sites can be done in several ways, but most methods will involve FTP client software and IP scanning tools. File Transfer Protocol, or FTP, has been standardized to run on Port 21 (command port) of most computers, and usually Port 20 (data port), but data ports can use virtually any port number. Administrators use FTP sites for transferring data either privately or publicly, but these sites are usually not listed with website traffic. The average computer user can scan for local or distant FTP sites in around 10 minutes.

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Network port scanner with port 21 results

Step

Download and install a network port scanning tool and FTP client. Trial versions may function for a short amount of time, but usually freeware tools are just as effective. CuteFTP or similar client software can allow access to FTP servers that lack web capability. Web browsers, like Internet Explorer or Firefox, can give limited access to some FTP sites by replacing the "http" in the URL to "ftp".

Step

Scan IP address ranges for port 21 traffic with the network scanner tool. Internet Protocol numbers run in octet series up to 254, so scanning from 23.23.23.1 to 23.23.23.254 could possibly scan as many as 255 computers. Increasing the range by changing the third set of numbers will scan more computers, such as 23.23.1.1 to 23.23.254.254. Scanning for port 21 will give a list of computers with this port open, and this port is strictly (95%) for FTP access. Scanning other ports can uncover FTP transfers, but without port 21 open it would not be likely.

Step

Load the IP address into the client, and set the username and password, if applicable. Many FTP sites will allow "anonymous" logins with a limited amount of access, and the client will have a check-box in its settings to log in with anonymous credentials. Another setting in the client that is relatively important is the "Active" or "Passive" mode selection, and setting it to "Passive" is adequate for most FTP usage.

Step

Using search engines and forums to look for FTP sites is recommended, and most forums or blogs will have search tools for keywords. Many people who host FTP sites and servers routinely post in forums about it, typically including IPs or URLs, to let others know about it. They can have many purposes, but normally are not illegal in nature, and easily located with simple text queries for "FTP site" or similar.