Hi we have k8s 1.27.1 with coredns compatible version 1.10.0 and k8s 1.26.3 with compatible version of 1.9.3.
When we upgrade our cluster 1.26.3 => 1.27.1 it was fine. When we rollback from 1.27.1 => 1.26.3 we have below fatal error from kubeadm. Any pointers? Is this a k8s issue? It is referring somewhere to 1.10.0 though kubeadm config file is updated to use 1.9.3 during upgrade(rollback) plan/init/upgrade phase.
"[upgrade/postupgrade] FATAL post-upgrade error: unable to get list of changes to the configuration.: start version '1.10.0' not supported",