I have a multi-wan setup with a gateway group consisting of WAN and WAN2, and failover from WAN to WAN2 if WAN goes offline.
The problem is that both WAN and WAN2 are connected to cable modems (an Arris modem for WAN and Netgear for WAN2), and each cable modem has the same IP address, which is 192.168.100.1. That's the default IP address for both modems, and there is no way to change it.
Every now and then, I'd like to access the web UI for either the WAN or WAN2 modem, and for some reason, when I type "192.168.100.1" into a browser, OPNsense always routes to the cable modem for WAN2, which is the Netgear modem. I can never access the Arris modem, which is the one connected to WAN, unless I unplug it from the OPNsense router and directly connect it to a laptop, which is a big hassle.
So here is what I'm wondering: since I have two devices in my network with the IP address 192.168.100.1 (which doesn't seem ideal but cannot be changed), is there a way from LAN side to tell OPNsense that I want to access the modem at that IP address that is connected to the WAN rather than the WAN2 interface?
After posting this, I figured out a workaround, which is to temporarily disable the WAN2 interface, after which the IP address 192.168.100.1 routes to the cable modem for WAN. So, this is solved.