Why not use DNS over HTTPS (DoH)?

51 Bogdanp 54 6/8/2025, 8:36:56 AM bsdhowto.ch ↗

Comments (54)

elashri · 2h ago
I think one way or another you will have to trust some entity with your DNS. Unless you are willing to use tor all the way on OS level. Even running your own recursive DNS resolver will leak your IP to root servers. Put VPN in front of it and know you trust this VPN company (kudos Mullvad).

And abusing https is for a good reasons. Blocking ports 53 and 853 is easy and many ISPs will do that.

The author also make it feel like the only option is to use cloudflare DoH on Firefox while that's the first option, there is also nextdns and custom field. There are many providers I would trust more like quad9 and Mullvad DoH.

I think the reasons why not to use DoH is the same for why not using public dns from providers you don't trust anyway.

Most of the people are happily using 8.8.8.8 and handing all their dns information to the biggest advertisement company in the world. Or wosre, using their ISP provided DNS.

btasker · 2h ago
> The author also make it feel like the only option is to use cloudflare DoH on Firefox

In fairness, the date on the post is 2018 - when Firefox first launched this, Cloudflare was the only option

elashri · 2h ago
Now that makes more sense regarding this point. I missed the date. I think the submission title needs (2018).
mercora · 2h ago
its funny you call out Mullvad in this specific case because its the one thing i really dislike about their VPN service. It wont route DNS to the root server, or any designated server really. They redirect DNS queries to their cache indiscriminately. which actually will harm the success of setting up a recursive resolver. I get this is done to prevent leaks, i would just like the option to opt out of it. been customer for many years now though. I use unbound semi recursively resolving using a forwarder with DNS over TLS. So Mullvad is not burdened with what i resolve and the forwarder not with information on who.
ls612 · 42m ago
I tried configuring Mullvad DNS on Firefox (last year) with DoH/DoT and it would randomly flake out and not resolve some domains (different ones each time) and the only way to fix it was restarting the browser. Cloudflare at least Just Works (tm)
xrmagnum · 2h ago
I find it problematic that this article recommends disabling DoH, which leaves users with unencrypted DNS — still centralized (e.g. to Google’s 8.8.8.8 or an ISP) and now vulnerable to man-in-the-middle attacks. Replacing one form of centralization with another while giving up encryption doesn’t improve privacy — it worsens it.

If the goal is to reduce centralization, a better approach would be to use encrypted DNS (DoH or DoT) with resolver rotation or randomization. That way, users retain privacy from local networks and ISPs without concentrating all DNS traffic in a single provider’s hands.

exiguus · 2h ago
If you're looking to implement encrypted DNS with multiple servers or providers, consider using unbound, which supports TLS resolvers and can operate in recursive mode. Alternatively, you might opt for AdGuard DNSProxy or dnscrypt-proxy, both of which support DNS over HTTPS (DoH), DNS over TLS (DoT), and DNSCrypt. You can run these tools on your local network or computer and configure your resolve.conf to point to them.
WhyNotHugo · 2h ago
Disabling DoH in your browser’s settings should make it fall back to you system’s resolver.

You’ll only be vulnerable to a MitM attack if your system’s resolver is insecure and also vulnerable to a MitM attack.

sammy2255 · 2h ago
(which all are by default)
creata · 3h ago
The points here aren't technically wrong, but it still feels like disabling DoH would be a reduction in security. For example:

> Cloudflare gets all your DNS queries.

That's true, but Cloudflare is more trustworthy than my ISP, and probably most people's ISPs.

> Complexity is the enemy of security.

That's true, but that's no reason to go from an imperfect solution to a nonsolution.

> there is DNS over TLS

That doesn't solve most of the issues that the author brought up.

> How does a modern company in the IT business earn money? By selling data.

Maybe I'm naive, but I thought they made money by using all the data they collect for better threat prevention, and from their paid services.

bigfatkitten · 2h ago
My ISP is bound by robust privacy, telecommunications interception and other legislation.

Cloudflare, on the other hand is based in a foreign jurisdiction that offers none of these protections.

zinekeller · 2h ago
> My ISP is bound by robust privacy, telecommunications interception and other legislation.

It really depends on which jurisdiction are you in, unfortunately. US ISPs are selling everything they can hover (including DNS information) to advertisers, and it is impossible to switch to another one unless you're lucky (because the monopoly is essentially maintained).

waynesonfire · 2h ago
And until TLS is made secure they'll continue to rape privacy by scraping your https traffic.
archerx · 3h ago
> That's true, but Cloudflare is more trustworthy than my ISP, and probably most people's ISPs.

Based on what?

ignoramous · 2h ago
> Based on what?

The bar is real low, mostly for the fact that ISPs are mandated by law in most if not all countries to track traffic flowing through their pipes.

Cloudflare provides relatively better privacy guarantees for the public DNS resolvers it runs: https://developers.cloudflare.com/1.1.1.1/privacy/cloudflare...

chgs · 2h ago
CF certainly less trustworthy than my isp which is shibboleth compliant. Or my vpn provider.

CF issues are dealt with “hope to get a post on HN trending”.

pacifika · 3h ago
In the UK you can typically pick from a dozen ISPs, some of which are more trustworthy
tankenmate · 54m ago
All of which have infrastructure already in place to hand over all DNS queries if requested by HMG.
ortichic · 2h ago
Can you also choose which company provides the physical infrastructure that connects to your home?
tialaramex · 2h ago
If you live in a city or other urban area, typically you have the option of the decoupled telco (BT Openreach) that more or less everybody has, the entity which bought all the cable television companies (Virgin Media) and usually a fibre-for-purpose Internet company that decided to do your city or region.

If you live in a rural area where people are co-operative, there might be a community owned fibre operator plus Opeanreach, otherwise just Openreach.

If you live somewhere very silly, like up a mountain or on your own island, your only practical option will be paying Openreach to do the work.

Edited to add, Notably: Only Openreach is usable by an arbitrary service provider. So if you want to pick your service provider separately, the actual last mile delivery will always be Openreach. And if they're small it won't just be last mile, Openreach also sell backhaul to get your data from some distant city to the place where the ISP's hardware is, you're buying only the, like, actual service. Which is important - mine means no censorship, excellent live support and competent people running everything, but the copper under the ground is not something they're responsible for (though they are better than most at kicking Openreach when it needs kicking)

chaz6 · 2h ago
CityFibre is only available through wholesale ISP's. Other smaller alt-nets (such as the one I work for - Netomnia (including Brsk/YouFibre)) is gearing up to provide wholesale access.

In the UK there are even aggregators like Fibre Café [1] that makes it easier for ISP's to connect through multiple networks.

[1] https://fibrecafe.co.uk/

chaz6 · 2h ago
If you are lucky, yes. For example, I have a choice between CityFibre (XGS-PON), Openreach (GPON) and Virgin Media (DOCSIS) as well as 2 different 5G networks. It is rare for a property to only be covered by a single wired network these days in the UK.
sudahtigabulan · 3h ago
His proposed alternative, DoT, still has one known peeper, and is easier to block. DoH, OTOH, looks like regular HTTPS traffic and is on port 443. So the "abuse" of HTTP is not unnecessary, you get something in return.

In some situations, DoT is fine. In others, it won't work, but DoH will.

om8 · 2h ago
I trust cloudflare more than my ISP, since I live in a place where internet is very state controlled.

Some of the websites just don't open without DoH.

dev_l1x_be · 33m ago
Two raspberries with Adguard combined with Tailscale is pretty safe and removes a nice chunk of garbage from the internet

https://adguard-dns.io/en/welcome.html

leosanchez · 27m ago
Why two ? For redundancy or am I missing anything?
exiguus · 2h ago
I concur and generally advise against using large corporate DNS providers. Instead, consider setting up your own DNS infrastructure, such as your own recursive servers, or opt for a trustworthy DNS provider like Freifunk or CCC, rather than Google, Cloudflare, or Quad9.

The advantages of self-hosting recursive servers include complete configurability, absence of censorship, tracking, and rate limits. However, like any self-hosting solution, it requires an investment of time and money. It's also important to note that DNS lacks an authentication layer, so for access restrictions, it should be placed within a private network or VPN.

The issue of pre-configured DNS over HTTPS (DoH) in many browsers and mobile devices can be addressed through firewall rules on your router.

For creating your own DNS infrastructure, I recommend dnsdist if you have ample time, though bind and unbound are also viable options.

For the past three years, I have been running dnsdist with recursive servers on two ARM VPS instances, costing around 14 EUR per month. This setup provides me with DNS over TLS (DoT), DoH, and other features. I use them with unbound (TLS) or dnsproxy and dnscrypt-proxy across routers, servers, and other machines. For mobile devices, I utilize DoH directly.

Previously, I used bind in recursive mode without any encryption beyond SSH tunneling or VPN.

Alternatively, I can recommend ffmuc as a DNS provider.

c0l0 · 2h ago
I also run my own recursive DNS server on a VPS I rent, but I freely share it with other users of the Internet. This causes my "personal" signal of queries to authoritative servers to effectively disappear, and I also (marginally) benefit from caching effects of other users' lookups.
exiguus · 1h ago
I haven't taken this step yet, but I have considered it. Could you recommend whether I should share the service on a list such as dnscrypt.info/public-servers?
c0l0 · 1h ago
I was not aware of such a directory existing in the first place :) I only advertise "my" service (it only implements DNS and DoT) through word of mouth in communities I participate in.
victorbjorklund · 1h ago
Are there any security risks with sharing it wiyh others?
c0l0 · 1h ago
Well, concerning technical risks, DNS Cache Poisoning[0] is a thing - but I keep the software implementing my recursive DNS service up to date very eagerly, so I guess the risk of falling victim to such an attack is rather low.

[0]: https://en.wikipedia.org/wiki/DNS_spoofing#Cache_poisoning_a...

creatonez · 2h ago
DNSCrypt has a list of DoH and ODoH resolvers other than Cloudflare: https://github.com/DNSCrypt/dnscrypt-resolvers
ggm · 4h ago
Eh. He doesn't discuss which public dns upstream supports dtls and in some sense it's just picking who snoops, ie he argues against cloudflare snooping but doesn't discuss who else might.

Run hyperlocal root, run your own dns.

His "don't move off 22 for ssh" is also just opinion. He argues "you will be found" but misses the experience of those of us running on shifted ssh is continuously validated by the visibly lower level of probes we see. He offers no mathematical analysis of how quickly a port knock sequence will be uncovered, and again dismisses it as infeasible and useless.

I've got nothing against strongly held opinions and these are his. But, form your own opinions too.

btasker · 2h ago
> His "don't move off 22 for ssh" is also just opinion. He argues "you will be found"

Worse than that, that post misunderstands it's own statement:

"Sure, you will see fewer attacks than before, but most of the attackers are no longer just stupid bots"

That's a *good* thing, because the move has reduced the signal to noise ratio. By getting rid of most of the crufty noise of the internet, you now know that anything hitting your logs now is more likely to be an actual threat than the poorly automated dictionary attack bots.

Moving SSH to a different port doesn't make the system much more secure (and definitely shouldn't be the only thing you do), but it does generally enable you to be more responsive.

mhitza · 2h ago
I'm going to mention again dns0.eu which does support DNS over TLS. I haven't looked in-depth but I'm pretty sure some corporate networks block it somehow because on some networks my Android phone fails to connect to it.
ignoramous · 2h ago
If privacy is your concern then dns0.eu is not "no logs" (like BlahDNS or Mullvad DoH/DoT are, for example). They share "anonymized intelligence feeds" with their partners: https://docs.dns0.eu/threat-intelligence-partners/anonymized...
throwaway81523 · 3h ago
Yeah I get almost no login attempts on ports other than 22. Should I even care about attempts on 22 though? They bounce off, and fail2ban blocks the IP after a while.

I sometimes think of putting my private servers on completely random IP addresses drawn from /64 IPv6 ranges. It should be near-impossible to find those by address scanning, unless I'm overlooking something dumb. Am I? It wouldn't surprise me.

tialaramex · 3h ago
An arbitrary IPv6 address is indeed not practical to find by scanning. However, unless you're willing to type in that 128-bit value each time you need it (which maybe you are) you'll advertise this address somehow and if you do that your advertisements can be read by others.

For example suppose you put my-private-server.vanity-domain.example in DNS with an AAAA pointing to your private server - "passive DNS" service means big DNS providers will sell the answers they saw when anybody (say, yourself, on somebody else's computer) asks AAAA? my-private-server.vanity-domain.example. They don't reveal who asked, so this isn't personal information, but they do reveal what the question was and its answer.

A long time ago we used this to build target portfolios, if we're going to sell your company our product X, this is way we can see that you already have products A, B and C, but not D, E or F so we look a bit smarter coming into the sale.

miyuru · 2h ago
For a real world example, I use IPv6 only SSH+public DNS and my fail2ban has 2 fails for a uptime with 285 days.
KwanEsq · 3h ago
Couldn't you just make my-private-server.vanity-domain.example a manual /etc/hosts entry to prevent advertising it?
kvdveer · 3h ago
You could. You'd only have the ability to log in from your own machine though. If that compromise works is very much dependent on your situation.
throwaway81523 · 1h ago
Yes, that's the idea of a private server. All the clients allowed to connect to it are mine, or at least authorized by me on a very small scale. Think of a backup server or a jump host.

Come to think of it, I could have a private DNS too. I haven't bothered with that.

hk1337 · 3h ago
Just as easy, you could just set the Host in your ssh config. Then you don’t have to deal with dns
j0057 · 3h ago
I agree that sooner or later your SSH port will end up on Shodan anyway. Putting SSH behind a Wireguard VPN solves this completely.
a022311 · 1h ago
That was indeed yet another one of Mozilla's well hidden moves to reduce our privacy. I've set up Adguard Home with a local recursive DNS resolver [1]. I haven't enabled encryption of the DNS queries, but I only ever connect through secure connections, so I don't mind. Sometimes queries are slightly slower or might fail (I'm guessing they time out), but I think it's really worth the extra privacy. I'm not really worried about leaking my IP to root servers, since at least they aren't run by an advertising company. (I hope?)

[1] https://github.com/semihalev/sdns

drykiss · 3h ago
They don't really say if DoT is safer. I'm more confused than informed by this article. Would've been nicer if they provided some proofs or data to back up their claims.

Also, does anyone know what's the safest option? And how to configure it for all our home devices?

arbll · 2h ago
Ah yes I'm going to disable DoH and go from trusting a central entity to trusting another central entity and everyone else on the wire.

Article is a bunch of strong opinion with nothing to back them.

deknos · 3h ago
is it possible to route DoH over generic HTTPS service when i only inspect a certain route? so i could have a generic https-server, where at some route, DNS requests are answered, other stuff just gives me a normal website?

because then we could use DoH for hiding our DNS requests..

btasker · 2h ago
Yes.

DoH requests go to /dns-query so you only need that path to proxy onto your DoH handler.

Some DoH clients will also allow you to specify a custom path, so you can also obfuscate the path by configuring client and server to use /foobar instead.

But, re-using an existing site does come at the cost of generating a bunch of extra log noise (fine if it's just you, not so fine if it isn't). If you don't have some kind of auth in place, you might also find that you suddenly come under a lot of load (when I ran a public DoH service, I eventually started getting a lot of traffic from users in an authoritarian country)

crabique · 2h ago
This is how it works already, the DoH endpoint is "/dns-query", both CloudFlare and Google route this endpoint to their resolver services, while the rest of the site (one.one.one.one or dns.google) is just a website.
spiffyk · 2h ago
Alright so the article's tl;dr says to not use DoH as it merely reduces the number of peepers to one (which firstly is a good thing and secondly also offers protection against UDP spoofing attacks)... then goes on to recommending DoT, which would suffer from the exact same (non-)issue, but also actually gets to the actual problem with DoH, which is that the HTTP part has no business being there and increases complexity, which I as a former DNS resolver implementor wholeheartedly agree with!

Why discredit the whole post by adding an irrelevant tl;dr?

jedisct1 · 3h ago
Anonymized DNSCrypt and Oblivious DoH are designed to keep your IP address hidden from resolvers, and there are DNS relays located all over the world. If you truly care about privacy, use anonymized DNS, not DoH.
tester756 · 2h ago
wtf is this?

>Is there an alternative way?

What about just using different provider that you trust?

What if I trust Cloudflare more than I do trust my ISP?