I've tried to set up SNAT to match INTERNAL network to a external ip, /usr/local/sbin/iptables -t nat -A POSTROUTING -o eth0 -s 10.0.0.0/16 -j SNAT --to-source 200.110.2.179 But that's working, it only works when i put: /usr/local/sbin/iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE eth0= external interface eth1= internal interface i've linux 7.3 kernel 2.6.3 andiptables v1.2.9 Could you help me please? Thanks