Log into mysql

mysql -u root -p

List users

select User,Host from mysql.user;

Should return something like the following

MariaDB [mysql]> select User,Host from user;
 +----------+-----------------------+
 | User     | Host                  |
 +----------+-----------------------+
 | root     | 127.0.0.1             |
 | librenms | localhost             |
 |          | localhost.localdomain |
 +----------+-----------------------+
 3 rows in set (0.00 sec)
MariaDB [mysql]>

Delete anonymous user

Note that there are two single quotes ‘ before the @ sign, not a double quote “

drop user ''@'localhost.localdomain';