Just a quick note for the unsuspecting:
I run two local DNSes, one recursive and one forwarding.
The forwarding one uses few services, like 1.1.1.1, 8.8.8.8, 9.9.9.9, etc.
One day I noticed inconsistent responses and started investigating. Turns out that by default 9.9.9.9 have "protection" and for your safety will lie and return NXDOMAIN or something else, for some dangerous domains, taking into account their definition of "dangerous". I am not saying that this is bad, probably lots of non-HN people don't want to run their DNS or anything related and just want a tablet that works because they don't even have laptop. It just hit me hard because I did not expected filtering on these servers.
Please correct me if I am mistaken, but unless there’s a local resolver for every single one of your clients, aren’t the DNS requests sent in plaintext to the upstream of your local resolver?
That might not be an issue for your situation, but I recall the benefit of something like Quad9’s offering is the encryption between client and their endpoint(s), particularly for untrusted ISP or similar.
> I prefer to run my own local recursive resolver.
Used to be fine. I stopped doing it when average TTL dropped to 300 seconds and it takes far too long for my local recursor to get the answer >100ms, when 3rd party resolver delivers in <10ms.
I tried Quad9 at our business for a while, about a year. I ended up moving to something else due to latency. I'm not sure if it was a routing issue or what but there were a lot of timeouts and slow responses. I have not had these issues with other providers.
When I run a mix of CF and Quad9 resolvers, Quad9 was consistently slower in response times when measured. But it didn’t make any perceivable difference in real usage.
> But it didn’t make any perceivable difference in real usage.
It can, it depends on the systems and user patterns. Example: if an end user is going to the same site over and over, those DNS responses are probably cached locally on the device, and may also be cached on any upstream resolvers.
OTOH if you were somebody without a Facebook account that went to Facebook.com to view a post from a link, you could easily have 120 different DNS lookups for various resources on that domain that haven't been DNS or web resource cached yet.
That might not be an issue for your situation, but I recall the benefit of something like Quad9’s offering is the encryption between client and their endpoint(s), particularly for untrusted ISP or similar.
Used to be fine. I stopped doing it when average TTL dropped to 300 seconds and it takes far too long for my local recursor to get the answer >100ms, when 3rd party resolver delivers in <10ms.
From AT&T fiber, Cloudflare’s 1.1.1.1 is always the fastest, though Quad9 is a very close second.
It’s interesting that it’s different from different ISPs.
https://www.privacyguides.org/en/dns/#recommended-providers
It can, it depends on the systems and user patterns. Example: if an end user is going to the same site over and over, those DNS responses are probably cached locally on the device, and may also be cached on any upstream resolvers. OTOH if you were somebody without a Facebook account that went to Facebook.com to view a post from a link, you could easily have 120 different DNS lookups for various resources on that domain that haven't been DNS or web resource cached yet.