Challenge 2

Use the following command to break something in the cluster

curl -s https://learn.exoscale.dev/cka/ch/set2.sh  | bash

The node worker1 seems to have some troubles. Identify the source cause and fix it.

Solution

The worker1 has the NotReady status

$ kubectl get no
NAME      STATUS     ROLES                  AGE     VERSION
master    Ready      control-plane,master   2d16h   v1.32.7
worker1   NotReady   <none>                 2d16h   v1.32.7
worker2   Ready      <none>                 2d16h   v1.32.7

The description of the node provide additional information

$ kubectl describe node worker1
...
Events:
  Type    Reason                   Age                From             Message
  ----    ------                   ----               ----             -------
  Normal  RegisteredNode           57m                node-controller  Node worker1 event: Registered Node worker1 in Controller
  Normal  NodeNotReady             25m                node-controller  Node worker1 status is now: NodeNotReady
  Normal  Starting                 24m                kubelet          Starting kubelet.
  Normal  NodeReady                24m                kubelet          Node worker1 status is now: NodeReady
  Normal  NodeAllocatableEnforced  24m                kubelet          Updated Node Allocatable limit across pods
  Normal  NodeHasSufficientMemory  24m (x2 over 24m)  kubelet          Node worker1 status is now: NodeHasSufficientMemory
  Normal  NodeHasNoDiskPressure    24m (x2 over 24m)  kubelet          Node worker1 status is now: NodeHasNoDiskPressure
  Normal  NodeHasSufficientPID     24m (x2 over 24m)  kubelet          Node worker1 status is now: NodeHasSufficientPID
  Normal  RegisteredNode           22m                node-controller  Node worker1 event: Registered Node worker1 in Controller
  Normal  RegisteredNode           96s                node-controller  Node worker1 event: Registered Node worker1 in Controller
  Normal  NodeNotReady             26s                node-controller  Node worker1 status is now: NodeNotReady

The Node in NodeNotReady status may indicate kubelet is having trouble. We have the confirmation checking the kubelet status with systemctl on this specific Node.

sudo systemctl status kubelet
...
○ kubelet.service - kubelet: The Kubernetes Node Agent
     Loaded: loaded (/usr/lib/systemd/system/kubelet.service; enabled; preset: enabled)
    Drop-In: /usr/lib/systemd/system/kubelet.service.d
             └─10-kubeadm.conf
     Active: inactive (dead) since Wed 2025-08-06 10:41:39 CEST; 2min 51s ago
   Duration: 23min 19.123s
       Docs: https://kubernetes.io/docs/
    Process: 170850 ExecStart=/usr/bin/kubelet $KUBELET_KUBECONFIG_ARGS $KUBELET_CONFIG_ARGS $KUBELET_KUBEADM_ARGS $KUBELET_EXTRA_ARGS (code=exited, status=0/SUCCESS)
   Main PID: 170850 (code=exited, status=0/SUCCESS)
        CPU: 31.077s

Let’s restart kubelet.

sudo systemctl start kubelet

The worker1 node should appear in the Ready status after a few tens of seconds:

kubectl get no
NAME      STATUS   ROLES                  AGE     VERSION
master    Ready    control-plane,master   2d16h   v1.32.7
worker1   Ready    <none>                 2d16h   v1.32.7
worker2   Ready    <none>                 2d16h   v1.32.7