I needed to setup an internal FTP server on a Debian server, so I used VSFTPD which is an excellent FTP server – see http://vsftpd.beasts.org
Anyway, it didn’t work all that well for me because I had a custom IPTABLES script running and of course needed to allow for FTP traffic. After fixing that it worked but something was still not right.
What I needed was an IPTABLES Module called connection tracking for FTP or ip_conntrack_ftp
In my IPTABLES configuration I added the following:
The the actual rule with a helper:
iptables -A INPUT -m helper –helper ftp -j ACCEPT
On the VSFTPD configuration side of things I added the following:
Now it works like a gem!!
More info on IPTABLES Connection tracking: