A quick search makes me guess/conclude that you likely have some extra fiber-to-RJ45 box somewhere ('glass-modem') and that its ethernet cable is going into RJ45 port number 4 of the SR203. If the 'Broadband' is for the telephone line (DSL).Pi5 connected to Sky Router SR203 on fibre FTTP.
That is quite common, I have one such box that I bought from the ISP because that was cheaper multi-year contract. It also has no dedicated WAN RJ45 port, according to manual and web-interface, RJ45_port4=WAN should work but it doesn't. Other firmware would enable it but it is closed-source, so the whole box is virtually electronic waste already for me after 3 years.
This 4port RJ45 might be 1 HW switch which just after reset and still un-configured acts as a 4port ethernet bridge. That would be a clarification for what you see.
Another thing is that in order to save costs, several of those ISP boxes have no RTC and small flash, they put the leases file in RAM, meaning reboot/reset/powercycle of the router makes all lease times in clients orphan. Might not be the case anymore nowadays, I don't know, I use my own router implementation for almost 10 years. Earlier on x86_64 (with RTC of course when bought in a shop), later on aarch64 were I added an RTC module, that makes various thing a lot easier.
Statistics: Posted by redvli — Sat Oct 12, 2024 6:49 am