eth1
ip 192.168.0.1
서브넷 255.255.255.0
 클라이언트 2000
ip 192.168.1.101
g/w 192.168.0.1
s/n 255.255.255.0
 이렇게...
 iptable -A FORWARD -i eth0 -o eth1 -j ACCEPT
iptable -A FORWARD -i eth1 -o eth0 -j ACCEPT
iptable -t nat -A POSTROUTING -o eth0 -j MASQURADE
iptables -A POSTROUTING -o eth0 -t nat -j MASQUERADE