Connection problems - New to FTP

Hi, I am fairly new to FTP and am having problems connecting to my home server. I have built a server at home using Windows 2003 and this connects to the internet via a NAT protected router. On the server I have bulletproof ftp server edition set up and most of my family can connect happily using this.

I found your SmartFTP v1.0.980 software recently and only intend to use it for personal use, whilst away from home. Since installing it, I have been experiencing patchy data connection problems which may be down to my NAT protected router. If I bring the server into the DMZ. I can connect without problems. When full protection is restored, your ftp client connects but then falls over when establishing a data port.

The NAT has been set up so that only ports 20 & 21 are open for the FTP connection. When Smart FTP connects, it seems to try other ports for the data transfer and this does not seem right.

This is a copy of the log. I have "*" out all personal data.

***********************************************************************************************
* SESSION STARTED AT 04.Feb.2004 10:28:04
***********************************************************************************************

Resolving host name *********.com...
Connecting to (***********.com) -> IP: **.**.***.*** PORT: 21
Connected to (************.com) -> Time = 41ms
Socket connected waiting for login sequence.
220 ****** FTP Server
USER *****
331 Password required for ******.
PASS (hidden)
230 User ***** logged in.
SYST
215 UNIX Type: L8
REST 100
350 REST supported. Ready to resume at byte offset 100.
REST 0
350 REST supported. Ready to resume at byte offset 0.
PWD
257 "/" is current directory.
TYPE A
200 Type set to A.
PASV
227 Entering Passive Mode (**,**,***,***,**,***).
Opening data connection IP: **,**,***,***,**,*** PORT: 8618.
A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
PORT ***,***,*,**,*,**
An established connection was aborted by the software in your host machine.
Connection closed.

***********************************************************************************************
* SESSION CLOSED AT 04.Feb.2004 10:28:32
***********************************************************************************************

I am concerned that the data connection does not use port 20/21 at any time and attempts to use random ports. I assume this is why my router is blocking this, but have been unable to set up SMTP, so that it connects regularly and correctly.

I look forward to any help you can provide.

Regards

Simon

Try to update the firmware of your router.

Thanks for reply, although my router is running the latest firmware.

I have now found out that the ftp client uses port 20/21 to handshake with the ftp server and then uses another port to perform the data transfers. It is this that the NAT is blocking (I assume). Is there anyway of setting the client software so that it will only set up a data transfer on specific ports. If this was possible, I may be able to open these ports too. Currently it uses random ports.

Cheers

Si

Yes, try reading https://www.smartftp.com/forums/viewtopic.php?t=6964

Mmm interesting thread but there is no newer firmware for my router. I will contact the router supplier, to see if they have come across this problem and are working on a fix.

Regards

Si

You can try to use port mode with local ip for that server, for some people that works.