master controllers starts producing the error "etcd cluster is unavailable or misconfigured"

Issue

• atomic-openshift-master-controllers service starts producing the error:

Jan 30 14:02:04 knakayam-ose33-master1.example.com atomic-openshift-master-controllers[2627]: E0130 14:02:04.514779    2627 nodecontroller.go:574] Unable to mark all pods NotReady on node knakayam-ose33-master2.example.com: client: etcd cluster is unavailable or misconfigured; client: etcd cluster is unavailable or misconfigured
...
Jan 30 14:13:46 knakayam-ose33-master1.example.com atomic-openshift-master-controllers[8138]: E0130 14:13:46.651637    8138 leaderlease.go:69] unable to check lease openshift.io/leases/controllers: 501: All the given peers are not reachable (failed to propose on members [https://knakayam-ose33-master2.example.com:2379 https://knakayam-ose33-master3.example.com:2379 https://knakayam-ose33-master1.example.com:2379] twice [last error: Unexpected HTTP status code]) [0]

• oc get node doesn't report the Node status correctly after this error happened.