Ubuntu was/is by far the more popular distro to use outside of the corporate world. There's a lot more blogs, container base images, tutorials out there because it was popular for tinkerers. This is also the reason it has now become popular inside the corporate world.
You may find it harder to find resources for AlmaLinux/CentOS/etc. if you are using the same methods for searching for resources as you would for a Ubuntu (or even Debian) based OS.
However, there are much better and more fully comprehensive training material out there for 'Enterprise Linux' distributions (RHEL, CentOS which means also AlmaLinux and Rocky) because of the widely industry accepted RH certifications.
So to wildly make broad statements: Ubuntu based distros are good for finding resources like blogs and tutorials that are aimed at people who are tinkering and just starting out, maybe from a dev background. EL distros are good for comprehensive training for people who probably have had "Sys admin" as a job title at some point.
> You may find it harder to find resources for AlmaLinux/CentOS/etc. if you are using the same methods for searching for resources as you would for a Ubuntu (or even Debian) based OS.
Not only that, but as soon as you venture outside of the "happy path", you'll run into difficulties if others haven't also solved those problems ahead of time, which can be the case with many DEB distros but isn't always so with RPM ones.
For example, in many RPM distros you'd typically reach for using Podman for running container workloads, maybe even use something like OpenShift (their MicroShift project still being in the works).
In contrast, on DEB you'd at least sometimes go with Docker, because it's widely known, widely used and still has lots of market share - offering such lighweight orchestrators like Nomad or even Docker Swarm out of the box, which still is an okay choice for getting a dev environment running on a few boxes with 8 GB of RAM, when you don't have a separate node for managing the cluster.
Now suppose that you decide to go with Docker on RPM. It's definitely feasible and has gotten better, but I recall just a few years back Docker having issues with SELinux and also the container networking utterly breaking because of firewall configuration. You had to use the masquerade option if I recall correctly, which definitely fixed the issue but also meant that the software package ships broken by default, in a sense.
On an unrelated note, I recently ran into an issue with one of the RPM distros a week back, where if the node has swap enabled and it runs low on swap memory, it's going to have the kswapd process start eating a lot of CPU resources and basically bring everything else on the node on a standstill.
Not to say that RPM is worse, the LTS EOL cycle alone is amazing, so I wish Rocky and Alma (As well as other distros) the best of luck! But I can also definitely recognize why many would stick with Debian or Ubuntu (or other DEB distros).
It seems like you might be conflating RPM distros with RHEL and it's clones, which seems to me a somewhat common thing to do. Suse distros are independent of Red Hat and have a different set of pros and cons, but I don't recall seeing or experiencing the ones you mention about docker or kswapd.
I'm yet to see anyone using SUSE or openSUSE (might be a regional thing), though I've heard good things about them! Thanks for pointing out that detail!
It’s totally impossible to google the solutions for Ubuntu because they’ve completely changed the way everything works, multiple times, so all the answers are wrong.
That may sound stupid or lazy, but there it is.