I have a CCR1016 sitting in a remote location, connected via AirFiber to the internet backhaul. Since we get the occasional failure of the primary backhaul, I connected a 4G router to the CCR, so it can use this connection when the primary goes down.
What I now need is for a way to find out the public IP the 4G router has - the router itself doesn't offer any dynamic DNS methods built-in.
Since the setup is [CCR 10.100.0.10] -> [4G Router 10.100.0.1] -> [4G Router public x.x.x.x] the normal scripts don't work, as the public IP will never be assigned to one of the interfaces of the CCR.
I cannot also see a way to use /tool fetch as it will always try to go out of the default gateway, which is fine during failover, but I want it to run always, so I can have a way to remote into the CCR at any time over the 4G link.