Why is DNS still hard to learn? • Hacker News Board

Re: Why is DNS still hard to learn?

#181

Post by laserbeam » Sat, Jul 29, 2023, 1:00 AM UTC

dgb23 wrote: post #41

laserbeam wrote: post #21

Here's what's cool about the article: - Presents some nice theories which make things hard to learn (infrequent use, poor tools...) - Describes how DNS tools could be improved. - Gives you a few gotchas for how one may shoot themselves in a foot with DNS. Here's what's a bit (not much) less cool: - I really have no clue if those things ACTUALLY make things hard to learn (because it's not a research paper on learning)…

As for the last point: Check out the author’s blog. She’s a real hacker and can convey technical things in friendly and simple terms.

Yup, I have no problem with the author or the work they do. I think it's cool. And there's still value in the article.

My only point is it slightly undermines this article per se. Claiming that something is hard to learn and immediately providing a thing that can teach it well is usually marketing. And that's all ok :).

Re: Why is DNS still hard to learn?

#182

Post by jodrellblank » Sat, Jul 29, 2023, 1:25 AM UTC

dahfizz wrote: post #133

chefandy wrote: post #56

Earlier quoted context omitted.

I'd conservatively estimate 90% of the people who make core FOSS software interface decisions haven't had to learn anything technical in an entirely unfamiliar domain where there existing mental models didn't apply in decades. Beyond that, many consider having learned these arbitrary, terse interfaces as a badge of honor, and for some reason thinks that makes them better technologists. I'll bet they'd be even better…

I disagree. The CLI is inherently a super-user oriented interface. The CLI needs to let an experienced user be as productive as possible. If you need a pretty UI with everything spelled out, you should go on GitHub and find a GUI that someone built on top of the core tool. But dumbing down the core tool is not the way to go. The --help message should be good, and the man page needs to be good, but the tool itself sho…

You are seriously taking the position that writing “received” instead of “rcvd” is “dumbing down”?

Re: Why is DNS still hard to learn?

#183

Post by knome » Sat, Jul 29, 2023, 1:28 AM UTC

wbl wrote: post #177

pests wrote: post #137

Earlier quoted context omitted.

Remind me again where this weird syntax came from for passing arguments?

- is allowed in domains

dash is only allowed in the middle. labels can't start or stop with it. so it wouldn't affect the command arguments.

    The labels must follow the rules for ARPANET host names.  They must
    start with a letter, end with a letter or digit, and have as interior
    characters only letters, digits, and hyphen.  There are also some
    restrictions on the length.  Labels must be 63 characters or less.

https://www.ietf.org/rfc/rfc1035.txt

it's more likely that in the late 90s they just made up their own argument parsing that they liked and the application has just used that ever since.

Re: Why is DNS still hard to learn?

#184

Post by 13of40 » Sat, Jul 29, 2023, 1:30 AM UTC

jvns wrote: post #159

tristor wrote: post #30

I don't agree with this article. I think DNS is something few people take the time to learn, but it's not actually hard to learn. One of the great things about DNS is that the system itself will tell you about it's internal state in response to queries. It's very easy to inspect a DNS server for a known zone and understand how it works, and there's very good tooling that's free and widely available to do this (like d…

Hello! I wrote this post and I have a couple of things to say about this "DNS is not actually hard" take. It took me many years to feel totally comfortable debugging DNS problems, and I wrote this post to explain why I think it was hard for me. I also used to think that "no, actually, it's easy!" was an encouraging response to "this is hard to learn". And I kind of get it! I love DNS! I think it is surprisingly simpl…

Just my 2 cents: I worked on the DNS in Windows Server back in the 200x's (validating the UI and back-end functionality, not dev work), so I did have to learn about it at one point and I recall that there was a vicious level of complexity to it compared to what we ask it to do. The 99% scenario is turning a domain into an IP via an A record. Next after that is doing the same with an MX record. Beyond that is this deep well of other things people thought someone might want to do with DNS, but that almost nobody takes advantage of in real life. So DNS is probably easy to understand if you're just concerned about the one or two first class scenarios, but if you had to implement an RFC-correct instance of a DNS server, it's a bit of a brain melter.

Re: Why is DNS still hard to learn?

#185

Post by [deleted] » Sat, Jul 29, 2023, 1:58 AM UTC

13of40 wrote: post #184

jvns wrote: post #159

Earlier quoted context omitted.

Hello! I wrote this post and I have a couple of things to say about this "DNS is not actually hard" take. It took me many years to feel totally comfortable debugging DNS problems, and I wrote this post to explain why I think it was hard for me. I also used to think that "no, actually, it's easy!" was an encouraging response to "this is hard to learn". And I kind of get it! I love DNS! I think it is surprisingly simpl…

Just my 2 cents: I worked on the DNS in Windows Server back in the 200x's (validating the UI and back-end functionality, not dev work), so I did have to learn about it at one point and I recall that there was a vicious level of complexity to it compared to what we ask it to do. The 99% scenario is turning a domain into an IP via an A record. Next after that is doing the same with an MX record. Beyond that is this dee…

[deleted]

Re: Why is DNS still hard to learn?

#186

Post by throw0101b » Sat, Jul 29, 2023, 2:01 AM UTC

haroldp wrote: post #176

throw0101b wrote: post #101

Earlier quoted context omitted.

Off the top of my head (haven't had to do zone files for ~2 years): * hostmaster@example.com -> hostmaster.example.com * NS records are usually hostnames (not sure if IPs are even valid) * Ditto for MX records ; also add a period to the end, otherwise example.net will get appended * Also appending with the www record See also: * https://linux.die.net/man/8/named-checkzone

Pretty good! :) Besides what was mentioned by others, there are two more mistakes in the SOA and one in each NS.

> mistakes in the SOA

I figured there was since (e.g.) the numbers looked 'off' (regular TTL vs. negative TTL), but couldn't be arsed to look up the exact SOA format.

Re: Why is DNS still hard to learn?

#187

Post by briHass » Sat, Jul 29, 2023, 2:05 AM UTC

gerdesj wrote: post #160

jl6 wrote: post #78

It's one of those things where there is a mismatch between how easy it seems to be, and how hard it turns out to be. We all use DNS every day, and it seems really easy. The everyday language of DNS is: domain names, lookups, IP addresses. This language is exposed in browsers for all to see, and through this exposure we develop a mental model of how we think it works. But under the covers there is a whole new language…

"that weird dot after the top-level domain" That weird dot is called root. Without it, a name is unqualified, with it the name is completely defined. That means that context is everything. Without the dot, a resolver might add the resolver's domain or parts of it, repeatedly. Now, you and I know exactly what: host.example.co.uk is supposed to mean but without the trailing dot a resolver could try to look up host.exam…

You might actually be surprised, or at least I was, that browsers -- and typically worse, IoT junk, still generally respect the DNS server(s) served to them via DHCP or they use plain ol' 53 to the hardcoded Google/Cloudflare standards. Some (like the Facebook Portal) are tricky enough to try DNS over TLS, but insofar as my big-list-of-common-DNS-IPs in the block rule is accurate, nothing reaches out over DoH unless explicitly configured to do so.

Like you, however, I see the writing on the wall. Being able to easily see (and block) how these devices/operating systems/apps relentlessly and obsessively phone home to upload as much telemetry as they can get their hands on is not something these corporations want. Eventually, they will all just use your connection for the bandwidth and pass everything over a VPN to hardcoded endpoints.

Re: Why is DNS still hard to learn?

#188

Post by syntheweave » Sat, Jul 29, 2023, 2:09 AM UTC

13of40 wrote: post #184

jvns wrote: post #159

Earlier quoted context omitted.

Hello! I wrote this post and I have a couple of things to say about this "DNS is not actually hard" take. It took me many years to feel totally comfortable debugging DNS problems, and I wrote this post to explain why I think it was hard for me. I also used to think that "no, actually, it's easy!" was an encouraging response to "this is hard to learn". And I kind of get it! I love DNS! I think it is surprisingly simpl…

Just my 2 cents: I worked on the DNS in Windows Server back in the 200x's (validating the UI and back-end functionality, not dev work), so I did have to learn about it at one point and I recall that there was a vicious level of complexity to it compared to what we ask it to do. The 99% scenario is turning a domain into an IP via an A record. Next after that is doing the same with an MX record. Beyond that is this dee…

This is the comment I wanted to make. DNS is one of those technologies that has a simple explanation - "it's indirection" - with consequential ramifications that turn it into someone's job. Most people will not interact with it often enough to know how to perform the job, so they remain hesitant and try not to do anything at all with it, because it burned them once before.

Git is analogous - most uses of Git are formulaic, and the underlying concepts are simple enough - but actually accessing the right lever to pull when disaster strikes is unclear and hard to experiment with. I'm in this latter category with DNS: I get it at a high level, but it's like a student who has only done the simple example project.

I'm of the opinion that we're at a good moment to redo the things DNS does with better separation of concerns by going towards "put those records on a blockchain, streamline it for known applications, reframe the hard problem around bootstrapping access to on-chain data". It's already been explored in varying degrees(e.g. Ethereum Name Service, Symbol namespaces) but it's not really something that has to be the monopoly of any specific chain.

Re: Why is DNS still hard to learn?

#189

Post by temporallobe » Sat, Jul 29, 2023, 2:19 AM UTC

tristor wrote: post #30

I don't agree with this article. I think DNS is something few people take the time to learn, but it's not actually hard to learn. One of the great things about DNS is that the system itself will tell you about it's internal state in response to queries. It's very easy to inspect a DNS server for a known zone and understand how it works, and there's very good tooling that's free and widely available to do this (like d…

Likewise, a lot of people know (and use) me for my supposedly deep knowledge of Git, even though it took me years to fully understand and feel comfortable enough with it so that I’m no longer terrified when using the CLI — I can cherry-pick and rebase with the best of them. YET, I still feel it’s a bit intimidating and that there’s some mysteries behind the internals I don’t fully grasp. I suppose like DNS, it does take time and effort to learn, and when I really think about it, it’s actually not that hard, but for some reason, so many devs struggle with it, mostly (front what I’ve observed) because it’s intimidating due to o it’s somewhat odd terminology and unintuitive workflow, but also because there are so many GUI/IDE tools that hide a lot of the complexity, which simultaneously good and bad.

Re: Why is DNS still hard to learn?

#190

Post by zhte415 » Sat, Jul 29, 2023, 3:25 AM UTC

saghm wrote: post #175

anyfoo wrote: post #166

Earlier quoted context omitted.

Maybe everyone sees this differently? Or maybe is more than one viewpoint to it. For example, if someone tells me that something is "actually really simple", and I did not get it yet, I tend to think that I likely (not certainly, but likely) have not found the right approach to that something yet, and once I found that way to look at it, things will resolve itself. But if people assure me that something is "hard to l…

> Maybe everyone sees this differently? Or maybe is more than one viewpoint to it. > For example, if someone tells me that something is "actually really simple", and I did not get it yet, I tend to think that I likely (not certainly, but likely) have not found the right approach to that something yet, and once I found that way to look at it, things will resolve itself. At least in my experience, people asserting that…

Your post reminds me of three things -

The nature of what's being learnt. Some things require a continuity - to understand B, prior A is needed (or helps, to understand faster).

The method of learning. Book/theory-based, or practical? For either, what's the nature of scaffolding (self, or via resources) to help leap the chasm? If testing one's self, what's the complexity and can that complexity be broken down into simpler (or more discrete) parts, (perhaps testing working better in smaller parts)? Perhaps A isn't fully (or at all) required to 'know' B, depending on how it's learnt. Which goes on to -

The nature of the learner (at that point for that task). Someone that's looking to solve a task, somewhat surface, or someone that's interested and will go deeper into edge cases or approach with greater curiosity?

[I'm skipping the nature of the learning/knowledge, since 'resolving DNS' is a pretty externally verifiable result. However it might be fruitful to consider the nature of the learning is not only 'resolving DNS', and even if 'resolving DNS' fails, learning always happens (intended/unintended, positive/negative, a can of worms there).]

You point out that 'easy' and 'hard' are motivators that might have unexpected, or the reverse, effects vs. intended, depending on the reader. When putting it into those 3 parts, perhaps this shows the usefulness of framing.