https://killercoda.com/killer-shell-cka/scenario/apiserver-crash

cd /home/vagabond/peak/kubequest/cka/compose/15-troubleshoot-controlplane

Kind cluster config (alternative setup):

# kind-config.yaml
kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
nodes:
  - role: control-plane
  - role: worker
  - role: worker

# kind create cluster --name demo-cluster --config kind-config.yaml

cd /home/vagabond/peak/kubequest/cka/compose/15-troubleshoot-controlplane/multipass && ./cluster.sh up
# SSH into master
multipass shell k8s-master
sudo su
cd /etc/kubernetes/manifests

cp kube-apiserver.yaml ~/kube-apiserver.yaml.bak ls -la ~/kube-apiserver.yaml.bak -> Add one -- this-is-very-wrong flag

ss -ltnp | grep 6443

SSH into worker

multipass shell k8s-worker

Or use kubectl from your host

export KUBECONFIG=/home/vagabond/peak/kubequest/cka/compose/15-troubleshoot-controlplane/multipass/.kube/config kubectl get nodes

https://killercoda.com/killer-shell-cka/scenario/apiserver-misconfigured he Apiserver manifest contains errors

Make sure to have solved the previous Scenario Apiserver Crash.

The Apiserver is not coming up, the manifest is misconfigured in 3 places. Fix it.

Log Locations

Log locations to check:

/var/log/pods
/var/log/containers
crictl ps + crictl logs
docker ps + docker logs (in case when Docker is used)
kubelet logs: /var/log/syslog or journalctl

Issues

Solution 1

The kubelet cannot even create the Pod/Container. Check the kubelet logs in syslog for issues.

cat /var/log/syslog | grep kube-apiserver

There is wrong YAML in the manifest at metadata;

Solution 2

After fixing the wrong YAML there still seems to be an issue with a wrong parameter.

Check logs in /var/log/pods. Error: Error: unknown flag: --authorization-modus. The correct parameter is --authorization-mode.

Solution 3

After fixing the wrong parameter, the pod/container might be up, but gets restarted.

Check container logs or /var/log/pods, where we should find:

Error while dialing dial tcp 127.0.0.1:23000: connect:connection refused

Check the container logs: the ETCD connection seems to be wrong. Set the correct port on which ETCD is running (check the ETCD manifest)

It should be --etcd-servers=https://127.0.0.1:2379

+

https://killercoda.com/killer-shell-cka/scenario/kube-controller-manager-misconfiguredhttps://killercoda.com/killer-shell-cka/scenario/kubelet-misconfigured

https://killercoda.com/killer-shell-cka/scenario/application-misconfigured-1https://killercoda.com/killer-shell-cka/scenario/application-misconfigured-2