FTP connection dies midway through transfer

[cmaxwell]

One of our servers is having a problem with FTP. It begins file uploads and after about 1MB of data transfer the connection drops.

If we disable the iptables firewall then it works fine.

I set the passive ports in /etc/proftpd.conf:

PassivePorts 49152 65534

And opened the ports in the firewall:

/sbin/iptables -A INPUT -p tcp -m tcp --dport 49152:65534 --syn -j ACCEPT

Other than this we don't have any other customisations on the firewall.

Any ideas? I'm guessing it's a problem with the firewall but find it very strange that it starts the file transfer then stops.

Thanks.

- Chris

 

[section31]

Does anyone have a sample iptables file that works well with ftp.. I'm having similar issues. Just a directory listing via ftp takes like 5 seconds with firewall on.

 

[cmaxwell]

We found that this problem was caused by the first rule in the firewall:

-A INPUT -p tcp -m tcp ! --tcp-flags SYN,RST,ACK SYN -j REJECT --reject-with tcp-reset

Try removing that rule from your firewall ruleset and it should start working.

- Chris