- cross-posted to:
- linux@lemmy.ml
- cross-posted to:
- linux@lemmy.ml
After a few conversations with people on Lemmy and other places it became clear to me that most aren’t aware of what it can do and how much more robust it is compared to the usual “jankiness” we’re used to.
In this article I highlight less known features and give out a few practice examples on how to leverage Systemd to remove tons of redundant packages and processes.
And yes, Systemd does containers. :)
Love me some systemd timers. Much more fun than cron.
- Sane handling of environment variables with
EnvironmentFile=
- Out of the box logging. Especially useful is the ability to
journalctl -f
to watch long-running processes, which I’m not sure whether possible with cron - The ability to trigger the service manually rather than setting the timer to
* * * * *
, then forgetting it’s supposed to run in a minute, get distracted, come back in 15 minutes
My only complaint is it’s a bit verbose. I’d rather have it as an option inside the
.service
file. The.timer
requires some boilerplate like[
(it… uh… triggers a service. that’s the description), and ].descriptionWantedBy=timers.target
. But these are small prices to payAnother thing I particularly like is
systemctl list-timers --all
and its overview of the timer statuses and when they’re going to run next.My only complaint is it’s a bit verbose. I’d rather have it as an option inside the
.service
file. The.timer
requires some boilerplate like[
(it… uh… triggers a service. that’s the description), and ].descriptionWantedBy=timers.target
.This can be solved through abstraction and automation.
In NixOS for example, you can declare a service that runs an arbitrary script every day like this:
{ systemd.services.your-service-here = { script = "echo 'Hello, world!'"; startAt = "daily"; }; }
This automatically creates a service file with the script in its
ExecStart
and an accompanying timer which runs daily and is part of thetimers.target
.Yep, I manage my servers and local machine with Ansible so I abstracted it with a role. This is indeed not that bad of a con because it’s still plaintext so automation is easy, but it’s still a minor issue ;)
- Sane handling of environment variables with
I never used Linux before systemd, so I never understood the drama. I use it a ton. Mostly to run my rootless containers via podman. I have a template service file for this, and I just change a few things, systemctl link, enable, and start. And voila. My container is running as a service that I can start and stop like any other service.
Admin dont like changes in their workflow and Systemd changes a lot of things, for better or for worse. That being said i do like how Systemd does things and wish for an overall better experience for linux not a worse one.
Yes, like
nftables
recently did change a LOT of things.nftables
? Is this a replacement foripchains
or something? :-|Ahaha you wish.
nftables
replacesiptables
and it has already happened in Debian 11.nftables adds a new tool, called nft, which replaces all other tools from iptables, arptables and ebtables. From an architectural point of view it also replaces those parts of the kernel that deal with run-time evaluation of the packet filtering rule set.
Read the complete explanation of the why is is happening here: https://developers.redhat.com/blog/2016/10/28/what-comes-after-iptables-its-successor-of-course-nftables
Replaces crontab with something auditable that actually makes sense and is easy to use
Is there an easier/quicker way than having to create a service unit and a timer unit by hand?
Maybe one of those tools? https://www.linux-magazine.com/Issues/2017/199/Systemd-Graphical-Tools or something Ansible https://github.com/vlcty/ansible-systemd-timers / https://yourlabs.io/oss/yourlabs.timer
But of I have to use separate tools… Can’t I just use a generator for a crontab? That’s not an advantage
I believe if you create a crontab on a systemd system, it actually synthesizes systemd timers from the crontab entries
i hate systemd and will do anything to not use it. the fanboys wont ack the many downsides (https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1988119 or https://news.ycombinator.com/item?id=25862927) or that it breaks the idea of how software should work. Lennart the jerk who sold his soul to red hat is just the tip of the iceberg. red hat streams start closing and now you who uses systemd will start losing. just wait for it …or keep telling yourself you are on lemmy but not on reddit because of the broke system?
Guys, downvotes are not the DISLIKE button, let’s not become reddit please
That comment is just spreading FUD. One of the links is just link to someone’s message saying they hate systemd. The other is just link to random (resolved) bug.
People aren’t disliking the comment, it’s actually terrible comment with no value.
I like systemd, but i’m glad you hate it so strongly. I feel much the same about snaps. Strong feelings one way or another make sure there are always alternatives, and that’s great.
Hmm… software has bugs. Still interesting how it mostly affected only people running on Azure. lol
What really breaks the “idea of how software should work” is Docker and all its bloat, dockerfiles, Docker Hub and the fact that newer developers aren’t able to ship anything without those overly bloated environments.
is docker more bloated than gtk? but yes, docker is sad too. :-(