KubeletClientCertificateExpiration #

Meaning #

Client certificate for Kubelet on node expires soon or already expired.

Impact #

Node will not be able to be used within the cluster.

Diagnosis #

Check when certificate was issued and when it expires.

Mitigation #

Update certificates in the cluster control nodes and the worker nodes. Refer to the documentation of the tool used to create cluster.

Another option is to delete node if it affects only one,

In extreme situations recreate cluster.