You buy a home router, open the admin panel at 192.168.1.1, go to set custom Pi-hole DNS servers… and discover the ISP router software has grayed out the custom DNS fields.
Consumer routers sometimes decide you don’t deserve administrative freedom on your own local network.
The Fix: Disable DHCP on the ISP router completely and let a local Raspberry Pi manage DNS & DHCP for your home network. 🌐