Launch FAQ: Can I run Kubernetes on Fedora CoreOS?

Yes. However, we envision Fedora CoreOS as not including a specific container orchestrator (or version of Kubernetes) by default — just like Container Linux and Atomic Host. We will work with the upstream Kubernetes community on tools (e.g. kubeadm) and best practices for installing Kubernetes on Fedora CoreOS.

@sanja , FYI, CoreOS(Container Linux) actually ships with wrapper scripts to run kubernetes(kubelet) on rkt. It even states the version of kubernetes. The same goes for etcd and etc. A typical way of ignition was using bootkube, not kubeadm. With CoreOS you didn’t even have to think about best practices on installing Kubernetes, it was just a matter of running another container instance.

I have an additional question, can Fedora CoreOS be kickstarted with bootkube?

Thanks!

I’ve been trying to install Kubernetes in a Fedora CoreOS (31.20191217.2.0) VM.
In the VM, I’ve installed the packages kubernetes-client, kubernetes-kubeadm, kubernetes-master, kubernetes-node.

This setup is using Docker (18.09.8).

kubeadm keeps having the following errors:

[wait-control-plane] Waiting for the kubelet to boot up the control plane as static Pods from directory "/etc/kubernetes/manifests". This can take up to 4m0s
[kubelet-check] Initial timeout of 40s passed.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10248/healthz' failed with error: Get http://localhost:10248/healthz: dial tcp [::1]:10248: connect: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10248/healthz' failed with error: Get http://localhost:10248/healthz: dial tcp [::1]:10248: connect: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10248/healthz' failed with error: Get http://localhost:10248/healthz: dial tcp [::1]:10248: connect: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10248/healthz' failed with error: Get http://localhost:10248/healthz: dial tcp [::1]:10248: connect: connection refused.
[kubelet-check] It seems like the kubelet isn't running or healthy.
[kubelet-check] The HTTP call equal to 'curl -sSL http://localhost:10248/healthz' failed with error: Get http://localhost:10248/healthz: dial tcp [::1]:10248: connect: connection refused.

Unfortunately, an error has occurred:
	timed out waiting for the condition

This error is likely caused by:
	- The kubelet is not running
	- The kubelet is unhealthy due to a misconfiguration of the node in some way (required cgroups disabled)

If you are on a systemd-powered system, you can try to troubleshoot the error with the following commands:
	- 'systemctl status kubelet'
	- 'journalctl -xeu kubelet'

Additionally, a control plane component may have crashed or exited when started by the container runtime.
To troubleshoot, list all containers using your preferred container runtimes CLI, e.g. docker.
Here is one example how you may list all Kubernetes containers running in docker:
	- 'docker ps -a | grep kube | grep -v pause'
	Once you have found the failing container, you can inspect its logs with:
	- 'docker logs CONTAINERID'

Has anyone managed to initialize Kubernetes with kubeadm?

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