ALTER DISKGROUP
  { { diskgroup_name
        { { add_disk_clause | drop_disk_clause }
            [, { add_disk_clause | drop_disk_clause } ]...
        | resize_disk_clauses
        } [ rebalance_diskgroup_clause ]
        | { disk_online_clause
   | disk_offline_clause
   | rebalance_diskgroup_clause
   | check_diskgroup_clause
   | diskgroup_template_clauses
   | diskgroup_directory_clauses
   | diskgroup_alias_clauses
   | diskgroup_volume_clauses
   | diskgroup_attributes
   | modify_diskgroup_file
   | drop_diskgroup_file_clause
   | usergroup_clauses
   | user_clauses
   | file_permissions_clause
   | file_owner_clause
   }
  | { diskgroup_name [, diskgroup_name ] ...
    | ALL
    } { undrop_disk_clause
      | diskgroup_availability
      | enable_disable_volume
      }
  }