Orbi LBR20 cannot connect to VPN when using LTE connection as primary

[pajus]

Hi,

I recently purchased Orbi LBR20 and also T-Mobile Hotspot plan.

So far internet access is working flawlessly. 

However that is not the case with the remote access.

The setup I did:

1. Enabled and setup DNS

2. Enabled VPN

3. Downloaded configuration files

However, cannot connect VPN or access router remotelly though mydomainname.mynetger.com: portnumber.

From what I can see so far, the problem is eventhough DNS return correct public ip (checked with nslookup in Windows command prompt, and whatismyip.com), T-Mobile assignes private IP to the router, and theredore making it unreachable from outside network. I was thinking to give up on this, but Access from Anywhere feature of the Orbi Android App is working when accessing from different network, which gives me some hope (might be false) that this can be set up.

For the record, I made the same VPN setup with the Nighthawk R7000p, which is connected to a Comcast gateway in bridged mode, and it is working. The only difference I could find is that in this setup R7000p gets assigned public ip.

[beetlejelly]

I was trying to do this as well.

Unfortunately, VPN, port forwarding, and ICMP replies are probably not possible using T-Mobile LTE mode.

I think that the "external IP address" that we see when we use a whatsmyip service is a T-Mobile WAN (Internet) port that hundreds/thousands of phones/devices are sitting behind. They do this because they can't give each person's phone/device a public IP address.
So in simple terms, your sim card is sitting inside of a T-Mobile LAN, and the external IP address that you see is the WAN port of this T-Mobile network. Your sim card has an internal address within this larger T-Mobile LAN and is thus non-routable from the external WAN IP address.

Public Internet --> External T-Mobile WAN IP --> your sim card with internal LAN address --> Orbi router.

When you connect your Orbi router to your Comcast modem and put the Comcast modem in "Bridged mode," Comcast is assigning a public IP address directly to your Orbi WAN (Internet) port, so it's routable, and you can forward ports, enable VPN, etc.

It would be great if there was a wireless provider that could assign a public IP address to your sim card. If anyone knows of a provider that offers this, I would love to know.