k0sctl kubeconfig does not use custom dataDir

[maxkochubey]

In case if there's custom dataDir defined for hosts[*] in k0s.yaml cluster config, for example:

k0s.yaml:

apiVersion: k0sctl.k0sproject.io/v1beta1
kind: Cluster
metadata:
  name: testk0s
spec:
  hosts:
  - role: single
    dataDir: /data/k0s
    uploadBinary: true
    files:
    - name: containerd-config
      src: ./containerd.toml
      dstDir: /etc/k0s/
      perm: "0644"
      dirPerm: null
    installFlags:
    - --debug
    ssh:
      user: testuser
      keyPath: ~/.ssh/id_ed25519
      address: k0s-single.example.com
  k0s:
    version: 1.27.2+k0s.0
    config:
      apiVersion: k0s.k0sproject.io/v1beta1
      kind: ClusterConfig
      metadata:
        name: testk0s
      spec:
        telemetry:
          enabled: false
        network:
          provider: calico
          podCIDR: 10.201.0.0/16
          serviceCIDR: 10.200.0.0/17

, k0sctl kubeconfig command fails with an error, trying to get the kubelet.conf file in default dataDir location:

# k0sctl kubeconfig --config k0s.yaml
level=fatal msg="read kubeconfig from host: remote exec error: failed to read file /var/lib/k0s/kubelet.conf: command failed: client exec: ssh session wait: Process exited with status 1"

k0sctl kubeconfig should respect the dataDir parameter values for control-plane host(s) or have the argument to override it.

For now, the only option to get a kubeconfig after the cluster have been deployed is something like

ssh -i ~/.ssh/id_ed25519 testuser@k0s-single.example.com \
"sudo /usr/local/bin/k0s kubeconfig --data-dir /data/k0s admin" > kube.config

[kke]

This may or may not fix itself for upcoming k0s versions due to k0sproject/k0s#3072 but of course it should be made to work for other versions through k0sctl.

[kke]

Note to self, check if #527 is related