search for: external_interface1

...only the rules for the internal interface and one of the external interfaces. The rules are the same ones for the three external interfaces. # global rule for all traffic iptables -A FORWARD -m state --state ESTABLISHED,RELATED -j ACCEPT # FTP rule iptables -A FORWARD -i $INTERNAL_INTERFACE -o $EXTERNAL_INTERFACE1 -p tcp -s $INTERNAL_LAN --sport $UNPRIVPORTS --dport 21 -m state --state NEW -j ACCEPT iptables -A OUTPUT -o $EXTERNAL_INTERFACE1 -p tcp -s $EXTERNAL_IP1 --sport $UNPRIVPORTS --dport 21 -m state --state NEW -j ACCEPT # FTP mark iptables -t mangle -A FORWARD -o $EXTERNAL_INTERFACE1 -p tcp --dp...