Im trying to test node crash scenarios in latest 4.19 nighty build cluster. I induce the crash by running echo c > /proc/sysrq-trigger from the node. After the crash is completed we have seen the node stuck in NotReady state. On further analysis we found out that kubelet  service logs it complains about /var/lib/kubelet/pki/kubelet-client-current.pem certificate and the reason was, that this file was empty.

I also find out, that there were some Pending CSRs:

csr-66nc8                                        81s   kubernetes.io/kube-apiserver-client-kubelet   system:serviceaccount:openshift-machine-config-operator:node-bootstrapper         <none>              Pending
csr-ldvdv                                        68s   kubernetes.io/kube-apiserver-client-kubelet   system:serviceaccount:openshift-machine-config-operator:node-bootstrapper         <none>              Pending

Once I've approved those CSRs, removed the empty file /var/lib/kubelet/pki/kubelet-client-current.pem and restart kubelet service, the nodes get's ready.

I have been doing similar testing almost every build of 4.19 but we are only seeing this issue in the recent builds (< 1.5 weeks)

OCP: 4.19.0-0.nightly-2025-07-02-143253

Near 100%

1. Deploy latest 4.19 OCP cluster     
2. Crash some of the nodes using echo c > /proc/sysrq-trigger     
3. Should be hitting the above mentioned issue on node recovery     

Node stuck in NotReady because of certificate issue 

Node should recover successfully