ALTER DISKGROUP { diskgroup_name { { { add_disk_clause | drop_disk_clause } [, { add_disk_clause | drop_disk_clause } ]... | resize_disk_clause } [ 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 } } ;