Our Rancher clusters were created not from RKE. I am storing my Rancher clusters etcd backups in S3 bucket. When I am trying to restore them, I am ending up in a problem. When I am using "rke up" and rke commands, it is popping up rke is not installed. When i tried to install rke in cluster CLI, there cluster.yaml file is not available. I can restore them ETCD backup's from rancher UI. But , I want to restore from backup's that are store in s3 bucket.