Clusterpirate

Intro Kubernetes utilizes TLS certificates to secure different levels of internal and external cluster communication.  This includes internal services like the apiserver, kubelet, scheduler and controller-manager etc. These TLS certificates are created during the initial cluster installation and are usually valid for 12 months. The cluster internal certificate authority (CA) certificate is valid for ten years. There are options available to automate certificate renewals, but they are not always utilised and these certs can become out of date. Updating certain certificates may require restarts of K8s components, which may not be fully automated either. If any of these certificates is outdated or expired, it will stop parts or all of your cluster from functioning correctly. Obviously this scenario should be avoided - especially in production environments. This blog entry focuses on manual renewals / re-creation of Kubernetes certificates. For example, the api-server certificate below exp