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Question : FTP issue through my Router?
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This is bizarre,
Okay.. I thought I had everything setup in my router cool, but obviously not. I'm using CesarFTP and previously tried Titan FTP with the same outcome; I can FTP to my Windows 2000 Server machine on my (LAN) side of my router with no problems, but when I try from the WAN side, I get a security error saying that I don't have access to the folder or the directory, and leaves the screen blank:
On the Windows 2000 Server machine I have IUSR_ setup for web access (see www.wellscore.net .. no problems on viewing contents via browser), and also I'm able to use the ASP Upload script to upload files to a directory through the browser on the WAN side with no problems, but I can't FTP files.
I have ports 20 and 21 open in my router for the FTP to run, so I'm out of ideas on getting this to work..
Router: Seimens 2602 2 port router; open ports:
80 - Web server
20 & 21 - FTP
System: Windows 2000 Server
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Answer : FTP issue through my Router?
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Do you have prot forwarding enabled on the router???
Passive and Active FTP
There are two types of FTP (File Transfer Protocol) these are Active and Passive
Active FTP
Pros (good for network administrators)
Cons (not so good for the client)
The FTP server will try and make a connection on a lot of high port numbers (these could well be blocked on the clients side Firewall)
Passive FTP
Pros (good for the client)
Cons (Not good for the network administrators)
The client makes the connection to the FTP server, and one will be a high port number that will almost certainly be blocked by the network firewall (server side)
Solution
To strike a happy medium, administrators can make their FTP servers available to many clients by supporting passive FTP; reserving a range of port numbers does this, in this way all other ports can be firewalled, thus decreasing the security risk
Luckily, there is somewhat of a compromise. Since administrators running FTP servers will need to make their servers accessible to the greatest number of clients, they will almost certainly need to support passive FTP. Specifying a limited port range for the FTP server to use can minimize the exposure of high-level ports on the server. Thus, everything except for this range of ports can be firewalled on the server side. While this doesn't eliminate all risk to the server, it decreases it tremendously. See Appendix 1 for more information.
*****Links*****
http://slacksite.com/other/ftp.html
http://www.cisco.com/en/US/about/ac123/ac147/ac174/ac199/about_cisco_ipj_archive_article09186a00800c85a7.html
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