FTP

[Orlando Reis]

Hi was wondering if someone can give me some help 
with a problem i'm having with iptables. I wan't to allow
people to connect to an internal ftp server.
But some how it doesn't work.
These are rules I' using for doing the job:

$IPTABLES -A tcp_allowed -p TCP -i $EXTERNAL_ETH0 --dport 21 -j ACCEPT
$IPTABLES -A tcp_allowed -p TCP -i $EXTERNAL_ETH0 --dport 20 -j ACCEPT
$IPTABLES -t nat -A PREROUTING -p tcp -d $EXTERNAL_IP --dport 21 -j DNAT
--to $INTERNAL_FTP:21
$IPTABLES -t nat -A POSTROUTING -o $EXTERNAL_ETH0 -s $INTERNAL_FTP -j SNAT
--to $EXTERNAL_IP

The clients can't even connect.

I do an ftp from an external machine with no nat(i.e.), a public ip.
and nothing happends.

Orlando

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