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Legacy Forums => Experienced User Forum => Topic started by: Steve Morris on October 07, 2001, 02:21:27 AM

Title: Port forwarding to FTP
Post by: Steve Morris on October 07, 2001, 02:21:27 AM

Hi
Can some one tell me if it is possable to forward incoming connections to another ftp server on the local network. I have gone throught the How to use port forwarding with an e-smith server and it does not seem to work.
I am using SME v5.
Any help would be appreciated.

Steve M.

Title: Re: Port forwarding to FTP
Post by: Anthony V on October 07, 2001, 10:09:44 AM

FTP and port forwarding are just not good friends.

Here is the problem....

The incoming connection comes in on port 21 without problem and
forms a control connection.
Then a second connection is made for data transmission using a different port
This port number is not permanently set.
It is possible to work out what range of ports would be used, and then
forward them all, but this is a massive security hole.

The long and the short?   FTP and firewalls are just not friends.

Title: Re: Port forwarding to FTP
Post by: J.Cugnoni on January 03, 2002, 09:56:50 PM

Hi,

If the FTP client is configured to run in PASSIVE TRANSFER MODE, the FTP server should be working even behind a NAT...

I have tried this with my current Freesco Linux Router (2.0 Kernel, mapping tcp:21 to an internal ftp server) and it works fine... but since I am a newbie in configuring Linux by hand (Freesco is really much simpler to configure for port forwarding), I haven't found the solution for E-Smith TCP port forwarding...

If someone can help me...