Cannot access my public ip from another t-mobile network

  • 15 december 2019
  • 4 reacties
  • 797 Bekeken


I recently bought a Huawei modem and a mobile data-only sim. I was able to setup port forwarding on it and could see my raspberry pi through public IP. However, if I try to access the IP from my phone, having another t-mobile connection, the request times out. This is bit strange as I can access the public IP from another phone with another provider (Lyca / KPN) but cannot access it from another t-mobile! It seems as if t-mobile is blocking access to it 's own IP.

Does anyone have any suggestions? Thanks for your time.

4 reacties

Reputatie 4
Badge +1

This seems like a strange explanation. Either the IP is publicly accessible: You can check this via 

Or it is not. 

There is no “in between” … So, maybe add more info about how you are testing what when you use the T Mobile connection? Are you sure you are not in the same LAN? 

Here are the screenshots. The first one is screenshot from my own phone, on t-mobile, and unable to access the public ip of the router. The other screenshot is from my another phone, on lyca mobile network, and able to access the public ip of the network. Obviously, this IP would probably change in a few hours, but the behavior doesn’t change. As seen in second image, my port 80 is open and accessible.

The public IP is indeed accessible, but just not from another t-mobile network. There’s no firewall as well, such that it might be blocking the requests. So, any explanations?

Reputatie 7
Badge +19


Are you using the smartsites.t-mobile APN?

Also are you sure that you are connected to the internet?

No, I’m not using smartsites.t-mobile APN. When I use that, public IP is not reachable via external network. I’m using ‘internet’ APN. Using this, I can ping my public IP from other network (lyca). And yes, I’m connected to internet. Been streaming movies over the same.