Hello everyone,
Recently I have returned to managing a kubernetes cluster in my homelab with Ansible on RHEL distros. Since I haven't touched to the installation stages since quite a long time I started to look for tutorials from the base installation to the cni configuration, MetalLB setup and metrics server installation.
In every single tutorial, I have seen major issues that made me pull my hair:
-
First and the worst, most tutorials obviously have the firewall disabled or tells you to deactivate it. Just. No. I know deactivating it makes everything much easier and many issues disappear as soon as you run a
systemctl stop firewalld. But if you want to teach correcty, you wouldn't recommend something that would make you fired on the spot. -
CNI installations are straight forward but miss important information for troubleshooting. Stuff like putting flannel interfaces in the internal zone or adding some direct forwarding rules to firewalld can be necessary but again, everyone and their mothers have their firewall off so they never talk about it.
-
In MetalLB, the configMap used by the speakers is not created automatically by the official manifest. Missing it is impossible as the speaker straight up do not start and the logs are straightforward. Yet I have never seen one tutorial mention it.
-
Again in metalLB, if the controller is on a worker node, webhooks are not accessible and you cannot configure the load balancer. It's rare-ish and easy to fix but again, never seen any mention of that
-
While Flannel, MetalLB, Weave, ... clearly state which ports you need to open for their solutions, tutorials never do (firewall? Someone?)
-
The metrics server has some ... Particularities (like the need to modify the startup arguments or the dnsPolicy). Those are easily found in the github issues due to how frequent they're but I can never seem to find a tutorial mentionning those extra configuration to do.
-
Various basic stuff like a worker node + a cni being needed for coreDNS and the master node to become ready. Or how to verify your deployment of ingress/cni/metalLB is working correctly. If you are familiar with Kubernetes, it's not too hard to find the solution to those but when most of your audience, it should be explicit to at least share a random nginx manifest to test if everything is good.
This is mainly a rant because it is crazy to see that a tutorial that is supposed to explain the documentation but faster is utterly useless because of course, you won't get any forwarding issues between interfaces if your device is an open bar.
And that most of them are like this.
So to everyone who also tried to follow tutorials for the set up of their clusterw what was your experience with them? Were they also useless or did you find a gem that didn't simply copy pasted the documentation and took screenshots of an working cluster setup without trying their guide?