this post was submitted on 27 Aug 2023
180 points (96.4% liked)

Linux

48077 readers
1069 users here now

From Wikipedia, the free encyclopedia

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

Rules

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago
MODERATORS
 

Ive been runing Debian 12 (kde) since bookworm was released and am loving it.

I have recently discovered Devuan which seems to be Debian without systemd - what is the benefit of removing this init system?

you are viewing a single comment's thread
view the rest of the comments
[–] [email protected] 157 points 1 year ago* (last edited 1 year ago) (18 children)

It's mostly opinionated. systemd is written in C, uses a consistent config, is documented well, has a lot of good developers behind it, is very fast and light, and does what it's doing very well. Since systemd also is split up into multiple parts, it still follows the "do one thing, do it right" philosophy.

There are some people that believe that systemd "took over" the init systems and configuration demons of their distro, and does "too much." It really does quite a lot: it can replace GRUB (by choice), handle networking config, all the init stuff of course, and much more.

However, I have lived through the fragmented and one-off scripts that glued distros together. Some distros used completely custom scripts for init and networking, so you had to learn "the distro" instead of "learn Linux." They were often slower, had worse error handling, had their own bugs, were written in various scripting languages like tcl, Perl, Bash, POSIX shell, etc. It was a mess.

The somewhat common agreed-upon init system was System V, which is ancient. It used runlevels, nested configuration (remember /etc/rc.d?), and generally, it was mostly used because it was battle tested and did the job. However, it is arguably esoteric by modern standards, and the init philosophy was revised to more modern needs with systemd.

You can probably tell my bias, here. If you have to ask, then you probably don't have a "stance" on systemd, and in my opinion, I would stick with systemd. There were dozens of custom scripts running everywhere and constantly changing, and systemd is such an excellent purpose-built replacement. There's a reason why a lot of distros switched to it!

If you want to experience what other init systems were like, I encourage you to experiment with distros like the one you mentioned. You might even play with virtual machines of old Linux versions to see how we did things a while back. Of course, you probably wouldn't want to run an old version of Linux for daily use.

It should also be mentioned that init systems are fairly integral to distros. For example, if you install Apache httpd, you might get a few systemd .service files. Most distros won't include init files for various init systems. You can write them yourself, but that's quite a lot of work, and lots of packages need specific options when starting them as a service. For this reason, if you decide you want to use a different init system, a distro like the one you mentioned would be the best route.

Great question, and good luck! 👍

[–] [email protected] 1 points 1 year ago (4 children)

I am fan of principles like KISS and “Do one thing and do it right”. From this point of view is systemd disaster because it is almost everywhere in the system - boot, network, logs, dns, user/home management… It’s always surprise for me if nothing breaks when I do upgrades.
I understand why systemd is here but I’m not at all happy to use it.

[–] [email protected] 26 points 1 year ago (3 children)

From this point of view is systemd disaster because it is almost everywhere in the system - boot, network, logs, dns, user/home management…

That's almost like complaining that GNU coreutils is a disaster from KISS point of view because it includes too many things in a single project - cat, grep, dd, chown, touch, sync, base64, date, env... Not quite, because coreutils is actually a single package unlike systemd.

The core systemd is big (IMHO it needs to be in order to provide good service management, and service management is a reasonable thing to include in systemd), but everything you listed are optional components. If your distro bundles them into one package, that's on them.

[–] [email protected] 1 points 1 year ago (1 children)

Systemd includes many complex things, coreutils includes many simple things. And coreutils are ported to many different OS’es, systemd is linux only. Ask why?

Lets imagine, my linux distro runs with openrc/upstart and I like systemd-journal features. Am I able to run system-journal without any other systemd components running?

[–] [email protected] 1 points 1 year ago (1 children)

(...) systemd is linux only. Ask why?

It is well known that systemd's service management is built around cgroups, which is a Linux-only concept for now. Other OSs have their own ways to accomplish similar things, but adapting to that would require huge changes in systemd.

Am I able to run system-journal without any other systemd components running?

No, the only part of systemd project that doesn't depend on systemd core is systemd-boot. And there's also elogind, which is an independent project to lift systemd-logind out of systemd.

But honestly, I don't see the issue here. You can't use systemd's components elsewhere, but your previous complaint was the opposite - that systemd is everywhere, as if you were forced to use networkd, resolved (which pretty much no distro uses AFAIK because it's way worse than other DNS resolvers), homed, timedated etc. when you use systemd as init.

Also, I have a correction for my previous comment: systemd-journald is not an optional dependency, as it's used as a fallback if the configured log daemon fails. I've only learned after writing that comment.

[–] [email protected] 2 points 1 year ago

I can see you are much more familiar with systemd and thank you for details.
But still I think systemd hardly follow KISS principle.

load more comments (1 replies)
load more comments (1 replies)
load more comments (14 replies)