Resolving Node Stuck in NotReady Due to Missing kubelet-ca.crt or kubeconfig During Cluster Upgrade

Issue

• Cluster Upgrade Issue: During a cluster upgrade, a node may become stuck in a NotReady state because the kubelet fails to start due to a missing critical file such as kubelet-ca.crt or kubeconfig.

failed to construct kubelet dependencies: unable to load client CA file /etc/kubernetes/kubelet-ca.crt: no such file or directory

• Access Restrictions: The node lacks SSH/SCP and oc debug command access, and the console screen does not allow copy-paste functionality, making traditional file transfer methods unavailable.