I have a linux server behind the ISP's cablemodem-router combo. With some hacking I was able to make the port forwarding work, and the DHCP exceptions in the udhcpd. But I wasn't able to do the NAT loopback: I can reach the server outside of my local network, but at home I can't. The router uses arno's iptables firewall, but the old version of it, so it hasn't got the nat loopback plugin. I want to make it work with the plain iptables.
Here is my current rule set: http://pastebin.com/SFNeY0Cu
I've found these commands:
iptables -t nat -A POSTROUTING -d 192.168.0.150 -s 192.168.0.0/24 -j SNAT --to-source 192.168.0.1 iptables -t nat -A PREROUTING -d $WANIP -m tcp -p tcp -j DNAT --to-destination $SERVERIP
Could someone explain me these commands? I think I understand the second, but the the first isn't clear to me. What is that 192.168.0.150? Or the 192.168.0.1? My home server is on the $SERVERIP, and my outer address is the $WANIP
Thanks for any help.