Now you need "complicated" things: prometheus, grafana, docker, etc.
I am a bit puzzled. Is it because sysadmin tutorials from 2000's are not showing up anymore in Google ? Why these tools failed to stay popular ?
For this kind of setup, prometheus and grafana are not complicated (close to 0 configuration), and docker mostly works out of the box on linux hosts, barring nftables shenanigans. You end up with something that "just works", is pretty, and does not require fiddling.
Technically I do find this overkill for "home network monitoring", but at least it does not require k8s so I won’t complain.
One would think that should be a hell of a low bar. It’s like having to choose a car and going “Trabant will do, at least it does not require a crew of seamen”.
I've been using InfluxDB at home just because of how easy it is to setup and use.
And the load of dozens to hundreds of data points in rrd is shockingly large. Our infrastructure utilization dropped by 30% when I switched from a Graphite/collectd setup to gathering MORE data more frequently with telegraf and influxdb.
I generally agree with the rest of your point, but the new-fangled infrastructure tools do have some merit and I look forward to seeing where we go with them.
I worked in FAANGS where simplicity really mattered over hype.
The best I can make of it is to treat docker as a package manager. All the dependencies in one place.
I ran K3s for a few weeks on ODroid hosts at home to get more k8s experience.
The cron gives you low granularity (and for some things, it may matter to measure things that changes in less than a minute), and flexibility (both in what you can measure and how you can arrange and correlate the different pieces of information).
Just works, sits neatly alongside a few extra services (managed via compose) in a little ARM dev board and has kept on ticking for around five years without any hassles using exactly those bits you mentioned.
The new things are shinier, I think, and on the other hand a lot of the old, simpler tools have become less relevant.
As an aside, I recall a younger self annoyed at the inability to get data out of RRDTool into a nice SVG chart. These days I just want the data in whatever format the best tool spits out...
I'd say it is easier and more powerful than rrd and cacti (used them like 10 years ago!)
With Prometheus and Grafana you can monitor an entire data center and add visualizations for metrics as you need them with no change to the monitored hosts.
TLDR: the old software stack could be made to do this, modern monitoring stacks do it out of the box.
All of the SEO skiddies are the ones pimping Kubernetes for your personal homepage and a few links.
And it shows. Lots of ways to build things fast, but nobody's building cool, lasting shit.
No way to make money with something that's well-built with the intention to last a life time. It's the "planned obsolescence" of the software world...