mysql> show engines;

+------------+----------+----------------------------------------------------------------+
| Engine     | Support  | Comment                                                        |
+------------+----------+----------------------------------------------------------------+
| MyISAM     | DEFAULT  | Default engine as of MySQL 3.23 with great performance         |
| MEMORY     | YES      | Hash based, stored in memory, useful for temporary tables      |
| InnoDB     | YES      | Supports transactions, row-level locking, and foreign keys     |
| BerkeleyDB | DISABLED | Supports transactions and page-level locking                   |
| BLACKHOLE  | NO       | /dev/null storage engine (anything you write to it disappears) |
| EXAMPLE    | NO       | Example storage engine                                         |
| ARCHIVE    | NO       | Archive storage engine                                         |
| CSV        | NO       | CSV storage engine                                             |
| ndbcluster | DISABLED | Clustered, fault-tolerant, memory-based tables                 |
| MRG_MYISAM | YES      | Collection of identical MyISAM tables                          |
| ISAM       | NO       | Obsolete storage engine                                        |
+------------+----------+----------------------------------------------------------------+

mysql>install plugin federated soname 'ha_federated.so';

mysql> show engines;

[mysqld]
federated

# /etc/init.d/mysqld restart

Warning: World-writable config file '/etc/my.cnf' is ignored

ls -la mysql.cnf