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The more I’ve learned about email while writing my own email server, the more I’ve realized I knew basically nothing about email when I started. Now, I’m at least somewhat knowledgeable, but god damn it’s so fucking complicated. Even something as seemingly straightforward as email has such a deep complexity that it takes years of study to even approach being an expert.
The single most useful thing I’ve learned doing this is that you should never assume you know a lot about a topic. There are a. always more things to learn, and b. always people who know more than you.
I have long said the only truly stupid people in the world are those who think that have nothing left to learn.
I like that line. I'm stealing it. Might paraphrase to fit the situation.
I did technical trainings, and I always used to say that the only stupid question is the one you don't ask.
"All I know is that I know nothing", Socrates.
With time I came to understand this as meaning that there's always far more left to learn than one could possibly know.
Maybe not the original meaning (the whole Cave Allegory apparently comes from him via Plato, so maybe it's about how the World is not really what we perceive), but it kinda fits.
This is, of course, a perfect example of D-K in action. This dude is writing his own email server, FFS, and he characterizes himself as, "at least somewhat knowledgeable".
I've read a bunch of the old RFC's for email services years ago, when you needed some of that info in order to do interesting things with sendmail. I figure that might have put me in the top 20% of programmers/admins/techies back in the day. But to actually consider writing an email server - no way. That's a different level of "at least somewhat knowledgeable" .
The 500 mile email comes to mind.
https://www.ibiblio.org/harris/500milemail.html
Next. Level. Troubleshooting.
Oh man, that’s such a good debugging story. I really like the can’t print on Tuesday bug too:
https://beza1e1.tuxen.de/lore/print_on_tuesday.html
"I'll just validate email addresses with a bit of regex. How hard could that be?"
Right!? Fun fact, this is a perfectly valid email address:
Running your own email server is a dark and lonely road that can only lead to crippling insanity. We can thank Google for that.
I’m definitely aware. I run an email service at https://port87.com/. Google is absolutely awful to deal with.
In many collectivistic societirs, humility is a virtue.
Job before that was like this. No one will believe me.
Family run, small business, run by well-off, conservative Southern Baptists. Sound like hell?
Admitting you made a mistake was a fucking virtue. You weren't forgiven, your mistake was ignored, except for everyone teaming up to figure a way to not let it happen again. No names, nothing said, let's figure it out.
I've never worked such a culture. My next job paid double. Fucked a thing up right off the bat, no big deal, was never trusted again. I could go on about that job, but on paper, it would sound like heaven. Had so much PTO I didn't bother tracking it, WFH, dev company.
I'd crawl on my hands and knees to get my office back with the Southern conservatives. And no one, not once, asked me about my beliefs or asked me to church.
Used to work in a place like this earlier in my career. It was a multinational, but not in the US. I transferred to another unit within the company completely different culture. It's a place by place kind of deal.
Why did you think email was simple? Every sysadmin knows this is the most difficult system, so we outsource it whenever possible
Well, maybe physical printers are worse. Both should be outsourced. They're both a PIA
I never thought email was simple. I thought it was straightforward. It’s not. It doesn’t matter if you follow the RFCs, you won’t have a working email server unless you listen to what the experts say.
For example, there are no RFCs about an IP address’ reputation, but that’s a real thing. When you sign up with your ISP, they’re not giving you a brand new IP address. Someone has used it before. They might have trashed its reputation, and there’s very little you can do about that. Then your emails will probably be blocked or delivered to the spam folder.