Pi-hole | IPv6 & Fritzbox

As default Pi-hole is processing IPv4 DNS requests. But nowadays your local clients receive also IPv6 addresses from your Router. So your clients are able to request IPv6 request, which would be bypassed your Pi-hole. This would also explain the “strange” behavior, why you’re getting furthermore some adds.

So to get rid of this state we have to do some settings, on our Pi-hole as well as on our Router (Fritzbox).

Fritzbox GUI

First of all we have to enable ULA addresses on our Fritbox, we need them to get always assigned on our local clients. ULA stands for “Unique Local Addresses” and the purpose is private. So those addresses are non globally reachable. It’s like the private classes of IPv4. –> This addresses are locally routable.

Enable ULA for IPv6 and create a Präfix, therefore you can use this website: https://unique-local-ipv6.com

Next step is to get an ULA IPv6 address on your Pi-hole, therefore you could restart your pi-hole. Then connect due SSH and print your ULA IPv6 address (ip addr show), I would also recommend to set this as a static address afterwards. This is necessary for our Fritzbox, because this will be entered as our new DNSv6 Server.

Also note to only serve DNS-Server within your DHCP for IPv6 settings.

Pi-hole GUI

At least, check your Pi-hole settings, they should like similar to this (i’am not using unbound anymore):

Reference: Original Pi-hole Doc: Pi-hole Docs

Cheers!