Nating

sanjibgupta · 05-15-2013, 06:48 AM

Hi
Presently I am doing SNAT for my local LAN IP to global ip except for the networks 192.168.0.0/16.

I am able to do so with
-A POSTROUTING -s 172.168.5.0/24 -d ! 192.168.0.0/16 -o eth0 -j SNAT --to-source 202.xxx.xx.xx

But now i also stop SNATING to 172.168.0.0/16 along with 192.168.0.0/16 from the local LAN.

Please help me to do so.

Thanking you
Sanjib Gupta

Ygrex · 05-15-2013, 11:10 AM

it is quite easy with a custom chain:

Code:

iptables -t nat -N sub-postrouting
iptables -t nat -A sub-postrouting -d 192.168.0.0/16 -j RETURN
iptables -t nat -A sub-postrouting -d 172.168.0.0/16 -j RETURN
iptables -t nat -A sub-postrouting -j SNAT --to-source 202.xxx.xx.xx
iptables -t nat -A POSTROUTING -s 172.168.5.0/24 -o eth0 -j sub-postrouting