10GB SFP+ and PiHole

Hey guys. I’ve recently updated to an X10 router in order to use a faster connection between my server and connected devices. I currently have PiHole running on a Pi4 and it’s set to be my DNS server and also has PiVPN, Cloudflared and DuckDNS installed. Besides some hiccups updating every now and then, things are working great. But, I’m afraid that once I setup my fiber connection and connect all the devices that I might lose network-wide Ad blocking.
Does anyone here have this sort of connection at home? Were there any configuration changes? What changes need to be made? Will the router’s DHCP static IP Addresses be respected with this setup, and will PiHole continue to work this way? In the past, I have never been able to configure PiHole to “listen on all interfaces” as it breaks DNS resolution once that is enabled. Maybe it has something to do with Cloudflare’s upstream servers, but I have no clue. It’s currently set to listen on eth0.
Any help or advice will be greatly appreciated as I’m embarking on this network change this weekend and would like to get as many tips/advice as possible.

If your RPi is connected only with ethernet cable then listening to eth0 should be the right option for Pihole.
Losing your network-wide DNS via Pihole may be a behave caused by misconfigurated DHCP settings. Make sure that you have only one DHCP server in your network. Choose the one thats fuctionality is best for the needs. The DHCP server must be able to configure your clients not just with an IP address, but with gateway und DNS addresses too. The same needs are for IPv6 too if used.
If IPv6 is beeing used on the RPi, the its best to let the router to be the DHCP server, but it must be able to configure the clients with RPi’s IPv6 (best is the link local address) as DNS. If not, it may be that the router uses its own and then clients are bypassing the Pihole via IPv6.

Hello. Well, currently the router is handling DHCP, and it’s working great. I was concerned about the new fiber interface causing issues with PiHole. I haven’t installed the fiber run yet or made use of the SPF+ ports, but was just wondering if I needed to make configuration changes once I switch to fiber.

I installed the switch last week and thankfully it comes with a dual boot mode; Router or Switch OS. With SwitchOS it behaves like any other switch and the router’s DHCP settings are respected.