So, this happened again, now Rancher is also not sticking to conventions: Add etcd status condition by vitorsavian · Pull Request #8724 · k3s-io/k3s · GitHub
In your case, please tell the provider of your Kubernetes to stick to conventions (using negative formulations for NodeConditions, e.g. MetaKubeNodeNOTReady…)
From Checkmk 2.3 on, you can manually map conditions, if your provider decides to introduce their own node conditions which do not comply with general conventions.
