DDNS on raspberryPI connected to mac shared internet

Question

Disclaimer - I understand that many of my problems could be solved by hooking up the pi straight to the router, but I've really become interested in solving this problem.

My setup:

DD-wrt cisco router --> mac --(shared internet)--> raspberryPi

I can ssh between my mac and the pi no problem. I can ssh into my mac using DDNS through noip, everything is fine. I can then ssh into the pi from the ssh session on my mac. This works for me, but im hoping to run a webserver on the pi (currently have barracudedrive installed). Ultimately, this will get a nice spot right next to the router. Until then, it would be nice to set up DDNS or some way to talk to the pi from the wan.

I've tried a couple solutions involving ssh port forwards on the mac, but i'm getting mediocre results. I've set up a DDNS host for the pi and have a port forward on the router from 8080 to 1024 on my local machine. Then, on the mac, i have a port forward from 1024 to port 22 on the pi. If i enter this into a web browser (only firefox, not chrome) i get that this address has a ssh v2 debian server. If i do this from my mac, i get nothing.

If someone has any idea as to how to get to this pi on shared internet from the wan i'd love ot hear it. Like I said, plugging into the router eliminates my problem, but I'd love to tinker from my mac for now.

Answer 1

There's a very good post about "double NAT" have a look http://www.graemenoble.id.au/post/48695277030/double-nat-explained-and-possible-solutions

Especially the section "Routing", you will learn that your modem needs to perform NAT for both ranges of IP (the one between the modem and the Mac and the one between the Mac and the PI).