Jan 22, 2021

Microk8s: No such file or directory: '/var/snap/microk8s/1908/var/kubernetes/backend.backup/info.yaml' while joining a cluster

 Kubernetes cluster with microk8s on raspberry pi

If you want to join a node and you get the following error:

microk8s join

Contacting cluster at
Traceback (most recent call last):
  File "/snap/microk8s/1908/scripts/cluster/join.py", line 967, in <module>
  File "/snap/microk8s/1908/scripts/cluster/join.py", line 900, in join_dqlite
    update_dqlite(info["cluster_cert"], info["cluster_key"], info["voters"], hostname_override)
  File "/snap/microk8s/1908/scripts/cluster/join.py", line 818, in update_dqlite
    with open("{}/info.yaml".format(cluster_backup_dir)) as f:
FileNotFoundError: [Errno 2] No such file or directory: '/var/snap/microk8s/1908/var/kubernetes/backend.backup/info.yaml'

 This error happens, if you have not enabled dns on your nodes.

So just run "microk8s.enable dns" on every machine:

microk8s.enable dns

Enabling DNS
Applying manifest
serviceaccount/coredns created
configmap/coredns created
deployment.apps/coredns created
service/kube-dns created
clusterrole.rbac.authorization.k8s.io/coredns created
clusterrolebinding.rbac.authorization.k8s.io/coredns created
Restarting kubelet
Adding argument --cluster-domain to nodes.
Configuring node
Adding argument --cluster-dns to nodes.
Configuring node
Restarting nodes.
Configuring node
DNS is enabled

And after that the join will work like expected:

root@ubuntu:/home/ubuntu# microk8s join
Contacting cluster at
Waiting for this node to finish joining the cluster. ..  
root@ubuntu:/home/ubuntu# kubectl get nodes
ubuntu   Ready    <none>   3m35s   v1.20.1-34+97978f80232b01
zigbee   Ready    <none>   37m     v1.20.1-34+97978f80232b01

1 comment:

  1. cannot run it on every machine ... microk8s.enable dns
    This MicroK8s deployment is acting as a node in a cluster.
    Please use the master node.