FTP site connections time out with large downloads 2

[pjewett]

We've setup an FTP site on a Windows 2000 box and since the day we set it up we've had the problem described below.

When anyone tries to download a large file or one that takes more than a few mintues, their connection is dropped (times out)...consistantly. MAC, PC, multiple FTP programs....it's all the same.

I know that FTP isn't typically a complicated animal so what could be doing this? Our firewall?

Any help is much appreciated.

 

[WhoKilledKenny]

In IIS under the FTP Site Tab it would be 'Connection timeout (in seconds):' But It should not kick you out while you are up/downloading as it waits for x amount of seconds of inactivity. I would suspect a setting on the firewall.

 

[pgaliardo]

Maybe a long shot here, but is it possible there are network/hardware prblems at the server and it only becomes evident during long downloads? For example, a bad NIC card that drops connections every 5 minutes. A person that takes 30 seconds to download a file won't be affected, but someone that tries to stay connected for 10 minutes for a larger file is affected?.
I agree the most likely culprit is the firewall, but check the NIC, cable, port on the switch, etc.

 

[pjewett]

What am I checking on the firewall?

 

[pgaliardo]

I am not sure what kind of firewall you are using, but see if there are any kind of inactivity timeout settings. Sorry I can't be more specific in where to tell you to look.

 

[PalmTest]

I once had a similar problem about an FTP site.
After a certain amount of downloading from the FTP site the connection was broken.
It came down to an "Output timer timeout" on the FTP server.

This timer was set a little bit too tight, so an FTP download over a slow link was broken, because the download time exeeded the timeout value. Remote sites with a faster connection never had any problems.
Setting the "Output timer timeout" to a higher value resolved the issue.

I do not know if this timer is set in Windows 2000 or in your FTP application or in the Firewall.

Can you check the FTP Error log for clues?
Do the firewall guys see simmilar things in their logging?