Ads are only blocked for 2h

[JulHeu]

Hi all,
I ran into a problem I unfortunately can't solve myself.

Background:

I set up Pi-hole in standard config on my pi3b.
IP4 and IP6 addresses are set to static.

For the first two hours or so, everything works fine and ads are blocked.

After this time I get an error and ads are no longer blocked

DNSMASQ_WARN Warning in dnsmasq core:

ignoring query from non-local network 2003:cb:4fff:22:7297:41ff:fe82:6a1d (logged only once)

Kernel:
Linux pi3 6.12.20+rpt-rpi-v8 #1 SMP PREEMPT Debian 1:6.12.20-1+rpt1~bpo12+1 (2025-03-19) aarch64

Expected Behaviour:

Ads should be blocked as queries are registered and detected by pihole.

Actual Behaviour:

Ads are no longer blocked and I see a massive decrease in queries registered (so they are bypassing the pi-hole)

Debug Token:

https://tricorder.pi-hole.net//S7h3TrRy/

Has anybody faced something similar and can give me a hint on how to solve this?

Cheers,

Julius

[JulHeu]

I solved it.

There were two factors to this problem:

1. IPv6 wasn't static and therefore the pi-hole could be bypassed; fixed this with the NetworkManager by setting the IPv6 of pi static and then using this as preferred dns server in router

2. I am running a second router as repeater to fully cover my flat (very thick brick walls...), which wasn't set to Access Point mode and therefore also handed out own IP adresses; fixed it by setting the router to access point mode

I hope this might help someone who is running into the same issues.

[Bucking_Horn]

@JulHeu

fixed this with the NetworkManager by setting the IPv6 of pi static

What kind of IPv6 address did you use?

If that was one of your Pi's IPv6 GUAs (range 2000::/3), then this may break once your public IPv6 prefix changes.

[JulHeu]

Thanks for reaching out!

Unfortunately, it is exactly this: 2003::/3.

Do you have any recommendations on how to do this better?

Just for context, I'm using a Speedport as the main router, and I've read on different pages that it may cause additional trouble and does not offer many customization options.