We are using the PepWave Surf on the go and it does not currently support Dynamic DNS function for Cellular connections. this would be a valuable feature if added
Dynamic DNS isn’t capable of working if the router to be dynamically DNS’d is behind some other NAT router, as then the router to be dynamically DNS’d has a private LAN IP address (10.x.x.x, 192.168.x.x, or 172.16.x.x-172.31.x.x) and will try to report that private IP to the Dynamic DNS service, and even if the dynamic DNS service didn’t reject it, it can’t work anyway.
When my ATT Velocity Mobile Hotspot (which is really a ZTE MF923) is acting as the WAN connection via USB, it assigns my Pepwave router a WAN IP address of 192.168.1.x, which means the hotspot is acting as NAT router. That also means that even if I fill out the dynamic DNS area (which exists under the USB WAN entry on my Pepwave) like I do for the Ethernet WAN connection, it can’t work due to the hotspot acting as a downstream NAT.