Hello, We have got a problem to setting iptables on a gateway. Topology :
Network with an hylafax server A gateway on debian with 2 network cards, one on network (tr0) and the other (eth0) on the next computer A computer (on $ OS who want to fax) We put ip_conn_track, and ip_conn_track_ftp on the kernel of the gateway We can make a telnet fax_server 4559, login as user and ... nothing else the iptables' rules : /sbin/modprobe ip_conntrack_ftp ports=21,4558,4557,4559 /sbin/modprobe ip_nat_ftp ports=21,4558,4557,4559 iptables -A INPUT -p tcp -i eth0 --dport 4557:4559 -j ACCEPT iptables -A INPUT -p tcp -i tr0 --dport 4557:4559 -j ACCEPT iptables -A INPUT -p tcp --sport 4557:4559 -m state --state NEW,ESTABLISHED -j ACCEPT iptables -A INPUT -p tcp --sport 1024: --dport 1024: -m state --state ESTABLISHED -j ACCEPT iptables -A OUTPUT -p tcp --sport 4557:4559 -m state --state NEW,ESTABLISHED -j ACCEPT iptables -A OUTPUT -p tcp --sport 1024: --dport 1024: -m state --state ESTABLISHED,RELATED -j ACCEPT iptables -A FORWARD -p tcp --sport 4557:4559 -s Faxaddr -j ACCEPT iptables -A FORWARD -p tcp --sport 4557:4559 -s Clientaddr -j ACCEPT iptables -A FORWARD --source Clientaddr -m multiport --protocol tcp --dport 4557,4558,4559 -j ACCEPT iptables -A FORWARD --source Gatewayaddr -m multiport --protocol tcp --dport 4557,4558,4559 -j ACCEPT iptables -A FORWARD --source Serveraddr -m multiport --protocol tcp --dport 4557,4558,4559 -j ACCEPT iptables -A FORWARD -m multiport --protocol tcp --dport 4557,4558,4559 -j ACCEPT iptables -A FORWARD -m multiport -m state --state RELATED,ESTABLISHED -j ACCEPT iptables -A INPUT -p tcp --sport 4557:4559 -j ACCEPT iptables -A INPUT -p tcp --dport 4557:4559 -j ACCEPT iptables -A INPUT -m multiport --protocol tcp --sport 4557,4558,4559 -j ACCEPT iptables -A OUTPUT -p tcp -o eth0 --sport 4557:4559 -j ACCEPT iptables -A OUTPUT -p tcp -o tr0 --sport 4557:4559 -j ACCEPT iptables -t nat -A PREROUTING -p tcp --dport 4557:4559 -j DNAT --to-destination Serveraddr iptables -t nat -A PREROUTING -p tcp --sport 4557:4559 -j DNAT --to-destination Clientaddr If you have advice ... David Dumortier [EMAIL PROTECTED]
