Im setting up a homelab and Im trying to figure out where the optimal location for the DNS and DHCP server (PiHole) is. The network is structured like this:
The majority of devices on the network are connected via WiFi (Phones, laptops, TV, smart home devices etc...).
The Xfinity modem is actually a modem/router device with WiFi disabled (xFi Advanced Gateway XB6)
I think the 'easiest' way is to think of them as seperate services. It doesn't actually matter where they are as long as the network segment's the same one.
"By default" - your asus router does 4 things. It acts as an AP, it acts as a firewall (which you want to retain - passing data from the wan), it does DNS and DHCP. These don't 'need' to run on the router. However if you're not using it on the router, you turn it off (but I think you know this already)
As long as there's a server doing DHCP and DNS the other systems should pick it up. I'd suggest running the pihole as a separate device rather than on the cluster, cause sometimes its difficult to bring up a container or vm cluster if it depends on dhcp or dns its hosting itself. As such either connecting it to the router or switch should be fine. You don't need much bandwidth so the 2.5Gbps vs 10 gig should be fine.
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