ethernet shield and ip forward

Using Arduino Networking, Protocols, and Devices
1

hello

i have an issue with the ethernet shield: i can't connect from outside my local network

i use debian jessie; arduino mega 2560 ship + ethernet shield w5100

i use a wifi key (wlan0) to access the internet through my phone (3g network share) and the shield is connected to the ethernet network device of the computer (eth0).

i try to setup the webserver example, i can access to it through the local network but impossible from the outside

i have tried many examples like thebelow to configure ip forwarding (without the nginx steps) but nothing working

so if i resume: i try to forward connections on port 8080 of the wlan0 (public) to 8080 of the ethernet shield 8080 through eth0 (private) ; doing this by adding iptables rules and including ipforwarding in the /etc/sysctl.conf

so what i understand is that my debian is the router and normaly it should accept connections in 8080 port

am not a pro in networking , so maybe am missing something in the whole picture??

am stuck in this since few days, and i can't see the exit.. if there's any help, i would apreciate it

2

so what i understand is that my debian is the router and normaly it should accept connections in 8080 port

A bit above that you told us that you connect to the Internet by your phone, so not the linux box is the router but your phone is the router. And even more unfortunate: many mobile providers don't use public IPs on their networks but us one huge NAT device for the complete cellular phone network. If that's your setup your Arduino will never be accessible by the Internet.

3

hi,
thank you for helping me, i could stay stuck with this long time

so if i setup the phone forwarding, that would work?

i didn't get the point with public IPs and huge nat device?

4

so if i setup the phone forwarding, that would work?

Probably not.

i didn't get the point with public IPs and huge nat device?

That's what many mobile providers are using and that was just the explanation why your setup won't work.

You have to change to a fixed internet connection where you get a public IP and you have to configure your router to forward a port to your Arduino. That's quite difficult to set up if you don't have a medium networking knowledge, so it might be easier to send your Arduino data to some cloud service and point your client devices to that service. If that's feasible depends on your goal but you didn't provided that information to us yet.

5

the goal is to light on a led , have access to temperature sensor through network

the first purpose is to learn how to do this kind of things, i guess learning about basics of networking is important, so i don't mind digging/reading this field;

  • can you be more specific about why it won't work ? if i root/ip forward my phone? if i send all entries of port 8080 to the shield and the same in the other way? is the phone local address like 192.168.1.1 ? or am totaly wrong, not working like this?

  • a solution like ubidots ethernet library seems easier and functional, but my goal is to learn, i would like to know more about my devices , learn how to deal with them without going through a service, if it's possible

6
  • can you be more specific about why it won't work ? if i root/ip forward my phone? if i send all entries of port 8080 to the shield and the same in the other way? is the phone local address like 192.168.1.1 ? or am totaly wrong, not working like this?

I didn't expect that rooting your phone is an option for you. Depending on your provide this might work but to actually check you have to find out what IP number your phone has. If it's a private range IP (192.168.x.x, 10.x.x.x, 172.yy.x.x) you won't succeed even if your root your phone.

7

hi;

thanks for the help and understanding;

I've tried with a router which i could setup the ip routing and it worked from the outside network

I'll try the phone rooting and so on for later

thank you