does anyone know a clear explanation of **exactly* what happens when you send a packet to 8.8.8.8 from a docker container? (i *think* the packet goes out through the veth pair, gets SNAT-ed, and comes back through the docker0 bridge but I'm very confused about it)
found this great blog post thanks to @vaijab that shows how to trace a packet's journey with `perf trace` and I'm so happy right now blog.yadutaf.fr/2017/07/28/tra…
also I think this post by @iximiuz is the clearest explanation of container networking I've ever read (though it still doesn't feel simple to me :) ) iximiuz.com/en/posts/conta…
wrote up some notes on my attempts to understand how to use a bridge yesterday. some of it is probably wrong. jvns.ca/blog/2021/01/1…
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I run a business called Wizard Zines (wizardzines.com) where I sell short (20-28 page) books (aka "zines") on Linux, Git, HTTP, SQL, bash, CSS, containers, tcpdump, networking, and more
I spent most of October tweeting bash comics, and I’m excited to announce that my “Bite Size Bash” zine is coming out on Wednesday!
here’s a thread with a little bit about why I wrote the zine…
I have a friend who’s a super accomplished senior engineer who mentioned once that they find working on bash scripts really scary and demoralizing.
so, why do really talented programmers struggle with bash?
some problems with bash:
1. It's a weird & counterintuitive language 2. you probably don't need to write it that often, so you don't practice 3. the times you DO need to use it, it's often because something important (like a build) broke and it needs to be fixed RIGHT NOW
- at least in firefox, <input> & <button> are inline-block by default, not inline
- the width on a block element defaults to auto, not 100% (though it will often look like it's 100%)
- you can set the width on an inline element if it's a "replaced" element
this "replaced element" thing is really confusing (developer.mozilla.org/en-US/docs/Web…). I did some tests and it seems like in Firefox a textarea is `display: inline` by default, but it's a "replaced element" so you can still set the width in CSS
an important thing to me about my zine business is that 100% of the revenue comes from people buying zines.
I get asked all the time to write sponsored zines ("hey, could you write a zine about our product") and I always say no -- readers are the customer, not the product.
(which is not to say that sponsorships are bad! Lots of really good education work gets funded through sponsorships. I help organize a conference that we fund largely through sponsorships. It's just not what I do with my zines.)
also please don't reply to this with explanations of other ways I could take money from sponsors. Selling zines to people who want to know stuff is actually a really good business! I don't need extra sponsor income.