manila对nfs扩容时报错，可作如下修复

编辑mania/share/drivers/helpers.py 288 行

# class NFSHelper 的disable_access_for_maintenance方法：def disable_access_for_maintenance(self, server, share_name):    maintenance_file = self._get_maintenance_file_path(share_name)    backup_exports = [        'cat', const.NFS_EXPORTS_FILE,        '| grep', share_name,        '| sudo tee', maintenance_file    ]    self._ssh_exec(server, backup_exports)    local_path = os.path.join(self.configuration.share_mount_path,                                  share_name)    out, err = self._ssh_exec(server, ['sudo', 'exportfs'])    hosts = self._get_host_list(out, local_path)    for host in hosts:        self._ssh_exec(server, ['sudo', 'exportfs', '-u',                                        ':'.join((host, local_path))])    # self._ssh_exec(server, ['sudo', 'exportfs', '-u', local_path])    self._sync_nfs_temp_and_perm_files(server)