dbaio@raulzito:/root/scripts# ncftp baio
NcFTP 3.2.0 (Aug 05, 2006) by Mike Gleason (http://www.NcFTP.com/contact/).
Connecting to 209.126.254.192...
FTP Server ready.
Logging in...
User admin@baio.com.br logged in.
Logged in to baio.com.br.
ncftp /users/admin > ls
List failed.
ncftp /users/admin > quit




Tenho o nat no firewall..

iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE

E essas regras diferentes.. o  resto eh alguns bloqueios e redir... mas nada na porta do ftp..

iptables -A FORWARD -p icmp --icmp-type echo-request -m limit --limit 1/s -j ACCEPT
iptables -A FORWARD -p tcp -m limit --limit 1/s -j ACCEPT
iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A FORWARD -p tcp --tcp-flags SYN,ACK,FIN,RST RST -m limit --limit 1/s -j ACCEPT
iptables -A FORWARD --protocol tcp --tcp-flags ALL SYN,ACK -j DROP
iptables -A FORWARD -m unclean -j DROP
iptables -A INPUT -m state --state INVALID -j DROP
iptables -N VALID_CHECK
iptables -A VALID_CHECK -p tcp --tcp-flags ALL FIN,URG,PSH -j DROP
iptables -A VALID_CHECK -p tcp --tcp-flags ALL SYN,RST,ACK,FIN,URG -j DROP
iptables -A VALID_CHECK -p tcp --tcp-flags ALL ALL -j DROP
iptables -A VALID_CHECK -p tcp --tcp-flags ALL FIN -j DROP
iptables -A VALID_CHECK -p tcp --tcp-flags SYN,RST SYN,RST -j DROP
iptables -A VALID_CHECK -p tcp --tcp-flags SYN,FIN SYN,FIN -j DROP
iptables -A VALID_CHECK -p tcp --tcp-flags ALL NONE -j DROP