How to set up Sagemcom FAST 5290v2 (FWR226e) Fiber Internet Gateway Router?

I am transitioning my home office to a new Frontier Business Fiber Internet 500 (500Mbps up/500 Mbps down). I have been provided with a Sagemcom FAST 5290v2 router with an integrated WiFi hub (2.4GHz/5.xGHz/5G). I need a static IP address in order to have external access to my Fedora server. On my previous provider, I could attach my own edge router to the (cable) modem, but Frontier tells me I MUST use their router, because of the peculiar way they have implemented their static IP. I see that the router attaches to Frontier's regional network with DHCP. The static IP address is implemented th

Question by Lars Poulsen on Super User, licensed CC BY-SA. We show a short excerpt and link to the original thread as credit.