On Fri 13 Feb 2026 at 09:37:25 (-0500), [email protected] wrote: > Wow, false alarm -- I am thoroughly embarrassed [ … ]
No need. When you've spent twenty years typing 192.168.1.x, it's all muscle memory. But can you just clarify—are you saying that two computers connected to the TMO RJ45 ports can communicate via their 192.168.12.x static addresses? That would be useful to promulgate here.¹ We have an ISP-provided cable modem/router here that's similar in having two ethernet ports plus WAP. We don't have any VoIP, but I use your method 3, as outlined in my previous response to you here: lists.debian.org/debian-user/2023/04/msg01197.html IOW, the ISP device is treated as just a modem. Since then I picked up a $15 clearance Archer C7 router that is now the primary router, and both the other routers are now WAP repeaters and ethernet switches (we built several cat5/6 cables into the house). Our LAN uses 192.168.1.x addresses², and the WAN side of the Archer happens to get 192.168.0.x assigned by DHCP from the ISP device. Double NAT causes no addressing issues as the ISP device's WAP is not used. I don't see any performance penalty. As for the second ethernet port on the ISP device, I leave it connected to the Roku (ethernet&wifi) device that sits by it. The Roku prefers its WiFi connection to our LAN, but after an ISP outage, the direct connection can be useful for determining whether the ISP device has successfully logged in or not. (On one or two occasions, the service has gone down and come up several times before returning to a steady state.) ¹ We get marketing material about this 5G service. Their web pages are silent on this point. ² The Archer runs a DHCP server for the twenty devices, and our computers have a "copy" of the address table in /etc/hosts. As for routing tables, there's nothing to do. Cheers, David.
