cinder/control/backend/nfs.yml

parameters:
  _param:
    cinder_nfs_local_path: /var/lib/cinder/nfs
  cinder:
    controller:
      default_volume_type: nfs-driver
      backend:
        nfs-driver:
          engine: nfs
          type_name: nfs-driver
          volume_group: cinder-volume
          path: ${_param:cinder_nfs_local_path}
          devices:
          - ${_param:cinder_nfs_host}:${_param:cinder_nfs_remote_path}
          options: ${_param:cinder_nfs_mount_options}