Creating a single node cluster uses etcd instead of kine for storage

[wvh]

When creating a single node cluster using k0sctl, the created cluster will use etcd for storage instead of kine, unless the storage option is specifically set to kine.

Explicitly adding a storage stanza will correctly use kine. Extract from k0sctl.yaml:

...
spec:
  hosts:
  - ssh:
      address: 1.2.3.4
      user: user
      port: 22
    role: single
  k0s:
    version: 1.23.6+k0s.0
    dynamicConfig: false
    config:
      apiVersion: k0s.k0sproject.io/v1beta1
      kind: Cluster
      metadata:
        name: monitoring
      spec:
        podSecurityPolicy:
          defaultPolicy: 00-k0s-privileged
        storage:
          type: kine
        ...

Without storage section, k0s will use etcd, even though the documentation says kine is the default storage option for single node clusters. I don't know if this is a bug with propagation of default values or simply a documentation issue.

$ k0sctl version
version: v0.13.0-rc.2
commit: 39a3f13

[kke]

That's strange. The only thing k0sctl should be doing when using single role is to add --single to k0s install flags.

[kke]

k0s config create creates a config with storage.type: etcd, but k0sctl should only do that when there's no spec.k0s.config at all.

[kke]

This may actually be a problem in k0s, if you provide a partial config to a cluster with --single, it will pick up etcd.

k0sproject/k0s#1707 related.

[till]

@kke I just tried this, when I run with single, it'll still start etcd. When I set storage.type: kine (no storage.kine.datasource), it will start with sqlite.

[twz123]

Is that still an issue? I cannot repro this using k0sctl 0.19.4 and k0s 1.31.2.

[till]

What exactly did you confirm?

[twz123]

What exactly did you confirm?

That running a node with role: single and no other storage settings via k0sctl uses kine by default.

[kke]

This should be fixed by #816