etcdadm VS cluster-api-provider-hetzner

Managed backplane is probably the most popular choice. I've used etcdmanager (now https://github.com/kubernetes-sigs/etcdadm) with success.

Hetzner Cloud is officially supported, but that means setting up VPSs in Hetzner's Cloud offering, whereas this project was intended as a more or less independent pure bare-metal cluster. I see they offer Bare Metal support as well, but I haven't dived too deep into it.

I haven't used KubeOne, but I have previously used Syself's https://github.com/syself/cluster-api-provider-hetzner which I believe works in a similar fashion. I think the approach is very interesting and plays right into the Kubernetes Operator playbook and its self-healing ambitions.

That being said, the complexity of the approach, probably in trying to span and resolve inconsistencies across such a wide landscape of providers, caused me quite a bit of grief. I eventually abandoned this approach after having some operator somewhere consistently attempt and fail to spin up a secondary control plane VPS against my wishes. After poring over loads of documentation and half a dozen CRDs in an attempt to resolve it, I threw in my hat.

Of course, Kubermatic is not Syself, and this was about a year ago, so it is entirely possible that both projects are absolutely superb solutions to the problem at this point.

For anyone interested in Kubernetes on Hetzner, there's a really interesting CAPI provider being actively developed:

https://github.com/syself/cluster-api-provider-hetzner

Just a hint running ML Workloads on Hetzner is pretty cheap! You could use for managing k8s: https://github.com/syself/cluster-api-provider-hetzner

we (Syself) release Cluster-API Provider Hetzner v1.0.0-beta.16.

ah okay they come from the upstream cluster-api project. The caph project implements only the infrastructure provider part of Cluster API.

you can easily use it with https://github.com/syself/cluster-api-provider-hetzner

I would use cluster-api-provider-hetzner from Syself.