Systemd's Nuts and Bolts - A Visual Guide to Systemd

medium.com Just a moment...

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If you’re a new or intermediate Linux user or sysadmin, you might have felt an odd fascination with the myth of systemd. I invite you to this deep dive into systemd's nuts and bolts. I'm not gonna beat around the bush: It's a hairy business, it will be hard, but I promise juicy and satisfying rewards if you keep pumping through this guide.
Let’s start by uncovering the “D” of systemd, the secret sauce that doesn't get the love it deserves: D-Bus.
Okay, those innuendos have to be intentional!
- Take a non-stop Linux box where even the kernel can be patched while it's hot
  Glance at d-bus sideways
  Now you must reboot.
- Thank you Ted, that's the joke.

systemdeez nuts!
- This is the beauty of open source. If you wrote an app called “eeznuts” and mad it something everyone needed, eventually a sysadmin somewhere would get to explain that joke to a stiff EVP, and they’d both have a good chuckle about it.
- Ha! Gottem.

I started reading that because I want to learn more about systemd and ended up wanting to go back to DOS. Presumably it all makes sense, but when I tried to read it my brain stopped working and my eyes slid off the bottom of the screen.
I don't know why but I just found it incomprehensible.
- I have yet to read this, but. But the first part is like the internals of systemd, you won't immediately need it.
  If you want to make use of systemd, you can skip directly to where it explains unit files. You'll soon see just how much it can do for you
- I don't know why but I just found it incomprehensible.
  #alwaysHasBeen, but for us graybeards the confusion has been "this is a solution with no problem" and "it's eaten WHAT now?"
  
  As a proper "gray beard" myself the utility of systemd vs. sys-v init scripts has always been blindingly obvious. 🤷

Great article! This helped me understand a lot more about D-Bus.

i would read it, if medium allowed me...
- https://archive.is/20250710091307/https://medium.com/@sebastiancarlos/systemds-nuts-and-bolts-0ae7995e45d3

That title gotta be intentional

Why it is a guide, it's not a visual guide.

Informative and informal. Love it!

I've very barely dipped my toes in dbus before, and the option to have something else is on its face attractive (not a fan of XML and the late 90s/early aughties style of oop), but JSON for a system interface?
I mean, Kubernetes shows that yaml can work, but in this day and age I'd expect several options for serialisation, and for the default to be binary, not strings.
String serialisations are primarily for humans IMO, either as readers or writers. As writers we want something with comments (and preferably no "find the missing }" game), so for that most of us would prefer something like TOML if the data is simple enough, and actually Yaml for complexity at the level of Kubernetes—JSON manages to be even more of a PITA at that level.
But machine-to-machine? Protobuf, cap'n'proto, postcard, even CBOR should all be alternatives to examine
- 100%
  JSON is not the optimal solution for either humans nor for machines... it's a compromise in-between that is more complex to parse than most binary alternatives (and even some text-based ones, if the data can be represented in CSV tables for example), while also often requiring post-processing through beautifiers and similar to be able to visualize it cleanly for humans.
  There are situations where it's the format that makes the most sense.. like in the web, where you are already working with javascript anyway. But it's not a golden bullet to use everywhere.
  
  Yeah, JSON is essentially a side effect of having JavaScript already. It makes sense that it shows up a lot of places, especially web. But just like with JS, it's not really good, just ubiquitous.

the Millie Vanillie of vibe coding if you will..
- Systemd is the Kanye West of vibe-coding.

article has a typo. opinion discarded.
/s

Ayyyyy!
Love systemd thanks for the writeup 👍🏽

That was a lot of really good info. I've been having to deal with some more complex systemd configurations at work which has gotten me interested in the subject. This was a really good intro and will help a lot in my own self-hosted activities as well as work.
- Thanks bro, just doing my best to keep our kind employed and informed. Long live the machine whisperers

a slightly unrelated question. do the authors at least get paid for posting things on Medium? if not, why do that? I'm unironically curious. it's a bad platform no matter how you look at it: it's closed for unregistered readers, it's typesetting sucks ass... the only reason I could see, is if the authors actually get some of the ad revenue, in which case I'd much rather pay directly to the authors.
- Yes, I do get paid. Sometimes considerably (for what tech writing can provide).
  Indeed, writing tech articles on Medium has allowed me to get some extra income/free-time in between jobs, which I use to upskill myself and then share what I learn with the community (with some amount of friction regarding the paywall). This self-reinforcing loop is quite appealing to me, and - I would argue - aligns somewhat with my take on the Kantian categorical imperative.
  For what it's worth, I like the typesetting. Medium also has extremely good SEO, likely from some direct negotiation with search engines, I assume. Eventually I plan to move my tech writings to my own blog, with some sort of minimal ad system, no paywalls. Also, I usually unpaywall my tech articles after the window of high income dries up.
  I updated the post to use the "friend link" which should allow you to read for free. (I didn't realize you could edit the link on lemmy after publishing).
  in which case I’d much rather pay directly to the authors.
  All my stories have a link to my ko-fi at the end, but the income from that is significantly less than what I get from Medium directly.
  Edit: Thanks @hayk@lemmy.ml for donating! Much appreciated!
  
  re: Medium I was genuinely curious why people use it, thanks for the clarification.
  still as someone who writes only open source codes, it goes a bit against my religion, but I totally understand if your income depends on it! thanks for the text, and for the "friend link". as promised... ; )

Sorry American readers, we in the real world use soccer metaphors, we are manly like that, even our women
As a European reader I highly doubt all claims in that sentence. refe what?
Actually I would have thought its the Americans that do this.
- Hmm, you must be Germænic or nordic. You know, places in which the soccer ball freezes during winter before the invention of frost resistant turf
  
  eastern, or middle, depends on how you look at it. orbán is not representative, he's special

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