al posto di: iptables -t nat -A PREROUTING -i eth1:1 -p tcp --dport 25 -j DNAT --to-destination 10.0.0.1:25 usa: iptables -t nat -A PREROUTING -d IPALIAS -p tcp --dport 25 -j DNAT --to-destination 10.0.0.1:25 ciao m.