Question

We want to set up a VPN over our 4g kit, on our Foritgate router it uses DDNS to registry an external interface IP to our DDNS provider.

We have RUT240 that we have set up in passthrough mode to one of the interfaces on the Fortigate but it gives out a private ip address 10.72.22.xx  when I do whats my ip through the teltonkia it gives me a different addreess 82.132.245.xx   

We just want to have the public ip go through to the lan port so our Fortigate router can do DDNS with it.

Answer 1

Hello,

It appears that you are assigned with a private IP address from your ISP and you are under at least one layer of NAT in provider's network.

Just to make sure, you could you login to the router's WebUI, navigate to Network -> Interfaces -> General and check the IP assigned to mob1s1a1 interface?

If you are indeed given a private IP, you will need to contact you ISP. Some providers require to use certain APN values to provide you with a public IP, but you will need to enquire about that. 

Otherwise, you could consider using a VPN solution, which does not require a public IP. One such option could be ZeroTier. You can refer to this page for configuration example.

Best regards,