I responded to someone in comments on a post that may not get as much visibility, and wanted to share something that might help some others sail the seas but also while not sailing, too.
I referenced Quad9 DNS as probably one of the best private DNS you can use, Swiss based, no log, no tracking, no data to sell, etc. They also implement DNSSEC, DoH, DoT, QUIC, ECS (which you may or may bot want), malware blocking, content filtering, and maybe something else I’m forgetting.
Many DNS sinkhole apps, OSes, or systems can actually utilize Quad9 for your resolver while those systems also block ads. Below is my functional list of systems that I’m aware of, though I haven’t tested everything. I believe all are considered FOSS, too. If you don’t have a spare Raspberry Pi laying around, try running in HomeAssistant, Yunohost, ZimaOS (previously CasaOS), or others.
DNS sinkhole (Adblocking) apps:
Feel free to comment and add your own I’m maybe not aware of. I’m no software engineer, but I can read through some code, though not an expert, nor have combed through these personally. Usually I’ve tested/run at the recommendation of others over the years before my ban on Reddit (for shitting on AI).
Hope this helps!!
And your effort on providing the information is appreciated (I’ve already set up Quad9!).
Just one question:
What do you mean uBO can use Quad 9? Do you mean it can be set up as an alternate resolver instead of using the system? Because if so, that would be great for provisioning eg.: Firefox + uBO on corporate semi-locked platforms when I have to do so for support reasons. Is there a hidden config or something?
If you’re talking about a browser, Firefox I believe can config custom DNS, but idk about it working alongside the extension if the extension needs to use its own. For the browser, I use PrivacyBadger from EFF for cookie and tracker blocking and PortAuthority which blocks LexisNexis port scanning on sites like eBay, etc. My adblock is done through pihole. Pihole uses Quad9 for the resolver.
I’ve set up adguard as a docker container running on my homelab before but it felt like it slowed almost every device on my network to a crawl. The docker container was running on an ssd but the only thing I could think of was that it was slowing every device down because it was searching the list of disallowed domains each time for far too long. So I disabled it and went back to some “ad blocking” euro dns option on my router.
I am getting ready to bite the bullet again though now that discord is pushing there bullshit ads into the mobile app. Can’t stand that shit and apparently all the “quest” ads can be blocked by DNS.
What were you running it on? Pihole is basically the same thing and runs just fine on older raspberry pi hardware (I had it on a 2 or 3 before moving to an AdGuard VM).
It sounds like there may have been a configuration issue somewhere in your chain.
It was running on my old desktop, a good gaming computer a decade ago. So it should have been plenty fast enough I’d reckon. I have ran pihole successfully on a raspberry pi before so I may just look into setting that up again. I agree it was probably a configuration error on my end though.

