$ sudo /etc/init.d/nfs-kernel-server restart
 * Stopping NFS kernel daemon                                                                                                 [ OK ]
 * Unexporting directories for NFS kernel daemon...                                                                           [ OK ]
 * Exporting directories for NFS kernel daemon...                                                                                    exportfs: /etc/exports [2]: Neither 'subtree_check' or 'no_subtree_check' specified for export "192.168.2.0/24:/".
  Assuming default behaviour ('no_subtree_check').
  NOTE: this default has changed since nfs-utils version 1.0.x

exportfs: scandir /etc/exports.d: No such file or directory

                                                                                                                              [ OK ]
 * Starting NFS kernel daemon