Syntax
------

ALTER LOGFILE GROUP logfile_group
  ADD UNDOFILE 'file_name'
  [INITIAL_SIZE [=] size]
  [WAIT]
  ENGINE [=] engine_name

The ALTER LOGFILE GROUP statement is not supported by MariaDB. It was
originally inherited from MySQL NDB Cluster. See MDEV-19295 for more
information.

URL: https://mariadb.com/kb/en/alter-logfile-group/