Came here to post this same link but you beat me to it! Big Clive's videos are brilliant—highly recommend his channel to anyone remotely interested in electricity/electronics.
This is a fantastic and well-written guide, thank you!
I recently wrote a toy caching DNS proxy in Elixir, and I have a question which I’ve never been able to figure out. Individual DNS records for the same hostname can have different TTLs configured. For example, 30s for one record and 300s for another. As a caching resolver, what is the expected behaviour when the record with the shorter TTL has expired but the other has not? I chose to invalidate the entire thing and make a new query upstream, but I’ve always wondered what the “proper” behaviour should be.
Having multiple TTLs in the same record set is deprecated. [1]
If you would rather put them in your cache, instead of not allowing to request them through your server, you are probably best off, by taking the lower TTL and using that as your initial TTL. E.g. this is how an authoritative Knot instance would handle differing TTLs in a DNSSEC signed zone.
I haven't written a dns server so this might be stupid question, but why would differing TTLs be a problem? You'd need just to key your cache with (label, recordtype) tuple, right?
> No uses for this have been found that cannot be better accomplished in other ways. This can, however, cause partial replies (not marked "truncated") from a caching server, where the TTLs for some but not all the RRs in the RRSet have expired.
So the cache could be split up like that, but then it could produce partial results, which is worse than reducing the effective TTL.
The desktop app will let you scan QR codes that appear on screen.
When 2FA fields show up, the password autofill shortcut (cmd + \ is the default I think) will automatically populate them.
Agreed. I've used Vim as my editor for as long as I can remember, and combine it with make if a project needs some kind of compilation or post-processing step. The flexibility of using it alongside a powerful general-purpose text editor means you can basically do anything, without the need for an IDE. Even writing mobile apps, and you get a better understanding of what's going on "under the hood" as well.
We noticed this affecting tens of thousands of users on Zapier last night, causing us to wonder if we'd shipped a critical bug. Zaps using Google apps are still paused[0] while we wait it out.
We have considered this actually, and I think it will be something we look into more as our scale increases. As you say, we already have the communication infrastructure in place via Celery/RabbitMQ.
We haven't evaluated RQ specifically, since RabbitMQ is a core part of our infrastructure and we're really happy with it. We have experienced the pain of managing Celery, and considered alternatives a few times though! A post about our experiences there is on the list to write! :)
Ahh... For being on Rabbitmq, I suppose there are few other options. Without going into a blog post, why not Redis? Other than fairly sophisticated message routing... Any other reason?
