I've had the pihole working for a while now. However, the other day Frontier upgraded my equipment, which also included a new router and the pihole doesn't work now.
I have a feeling I know why it's not working, however, I'm not sure what I need to do to get it working again.
The pihole still thinks its' I.P. address is 192.168.1.18:
It looks like on the router you have the option of changing the local IPv4 range (they don't appear to be grayed out). In the Gateway, use 192.168.1.1, and in the range use the range 192.168.1.10 to 192.168.1.210. Then reboot the router and renew the DHCP lease on all the clients.
I'm not sure why Frontier has their router (Arris NVG468MQ Gateway) configured with the higher i.p. addresses? Maybe your local network is less likely to be hacked using higher i.p. addresses? Maybe it has something to do with their service? I don't know.
In any case, whatever their reason(s), I decided to leave the addresses as they are (for now), and I tried re-imaging the pi-hole. It took a while to re-image, reinstall, and reconfigure everything. And in the end, I still couldn't get it to work; even with the pi-hole using 192.168.254.10.
After all of that, I realized that even if I get it working, pi-hole is running on a Raspberry Pi 3 (Adafruit kit) which only has 100Mb ethernet. I recently upgraded my network to 1Gb ethernet and the thought occurred to me that the Pi 3 might slow everthing down since all traffic goes through it.
I could buy a new Raspberry Pi 4 which has a 1Gb ethernet port. However, I don't know if pi-hole supports Pi 4. I also don't know if the PiTFT display I'm using is supported by Pi 4, or if the case will even fit.
I finally got it working again! Apparantly there was a conflicting interface eth0 entry in my /etc/dhcpcd.conf file. Once I fixed that and changed the router to use the pihole, it works.
Also, it looks like my speed isn't really affected by the Raspberry Pi's 100Mb ethernet port.
As previously noted, none of the data traffic goes through the Pi-Hole. Pi-Hole sits on the network like any other client, but it only processes DNS requests, which are very low bandwidth.
The data traffic goes directly between the client and the router, with no involvement from Pi-Hole. If you ran a Zero W with Pi-Hole, you would see the same network performance, even though the Pi Zero W is on 2.4 GHz wireless.
unless you're an oddball like me who is putting all his network traffic through the Pi (with no adverse effects seen so far which includes multiple clients streaming youtube etc at the same time, vpn open to work etc etc) ;o)
