ftp / firewall

[Keith Floyd]

Hi

I have problerms with ftp and going throufg a firewall.

Using netstat -p tcp what pertinent info can I gleam from this, that may help me diagnose the problem


Thanks

Keith

[Mike McKinlay]

What are you trying to do? Outbound FTP to a server on the other side of the firewall, or inbound FTP to a server on your side of the firewall?

Is FTP enabled on the firewall? What kinds of errors are you getting?

[Berlene Herren]

You might need a program like Socks, available from
http://www.socks.nec.com

Berlene

[Kofi ARTHIABAH]

What firewall are you using. It sounds like you are having difficulties with PASV mode transfers...

[Rick Garland]

The firewall may be set to block the ftp traffic. Can you check to see if the ftp port is blocked? If so, you may want to look into the socks solution that Berlene mentioned.

[ESC Team]

It is possible that the port FTP uses
(usually 21) is closed. You will need to
contact the network administrator for your
site and check that this port is open. To
check that the FTP service is functioning
correctly, try connecting to another machine
on the same subnet. If this works, then
check that the firewall port is open.

[Keith Floyd]

thanks so far more info

ftp works - is constantly cron'd to send/rec. My issue is that quite often ftp seems to lock up.
I wonder whether it's due to TCP timeout etc, hence I wanted to interpret the netstat -p

thanks

Keith

[Andrew_4]

You might need to try doing a trace on the ftp protocol, between the two hosts you're ftp'ing (This is done by filter by IP address). You can do this via the nettl command.

It can be a little complex, so you're best to read the man page.

Andrew

[Kofi ARTHIABAH]

Keith,
If your ftp files are really really large then you could run to the TCP timeout problem causing it to fail. If that is the case, you would have to fix the TCP timeout on the firewall itself. BTW what firewall are you running? is it a proxy, or packet filter, or stateful?