iptables -t nat -A POSTROUTING -o $IFACE -j MASQUERADE
iptables -A INPUT -i $IFACE -m state --state ESTABLISHED,RELATED -j ACCEPT
auto lo eth0 eth1
iface lo inet loopback
iface eth0 inet static
address 192.168.1.2
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255
gateway 192.168.1.1
up echo 1 > /proc/sys/net/ipv4/ip_forward
up iptables -t nat -A POSTROUTING -o $IFACE -j MASQUERADE
up iptables -A INPUT -i $IFACE -m state --state ESTABLISHED,RELATED -j ACCEPT
iface eth1 inet static
address 10.1.1.1
netmask 255.255.255.0
network 10.1.1.0
broadcast 10.1.1.255