I wrote these instructions years ago, but couldn’t find them the other day. So I’m updating a few things and reposting here.

Make sure you have mysql in /etc/group. Normally the gid is 27.

It wants to put a file in /var/run/mariadb. Remember that this is a tempfile on rhel7. So you need to remake this directory on every boot. Create /etc/tmpfiles.d/mariadb.conf with:

# mariadb needs a directory in /var/run to store its pid file and args file
d /var/run/mariadb 0755 mysql mysql

After installing mariadb-server, need to set a password and delete all the default users that have no password.

# systemctl start mariadb
# mysqladmin -u root password 'new_password'

# mysql -u root -p
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| test               |
+--------------------+
3 rows in set (0.00 sec)

mysql> use mysql;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed

mysql> select Host,User,Password from user where user='';
+-----------+------+----------+
| Host      | User | Password |
+-----------+------+----------+
| comp      |      |          |
| localhost |      |          |
+-----------+------+----------+
2 rows in set (0.00 sec)

mysql> select Host,User,Password from user where Password='';
+-----------+------+----------+
| Host      | User | Password |
+-----------+------+----------+
| comp      | root |          |
| comp      |      |          |
| localhost |      |          |
+-----------+------+----------+
3 rows in set (0.00 sec)

Now need to delete those empty users.

mysql> delete from user where User='';
Query OK, 2 rows affected (0.00 sec)

mysql> select Host,User,Password from user where Password='';
+------+------+----------+
| Host | User | Password |
+------+------+----------+
| comp | root |          |
+------+------+----------+
1 row in set (0.00 sec)

mysql> delete from user where Password='';
Query OK, 1 row affected (0.00 sec)

mysql> select Host,User,Password from user;
+-----------+------+------------------+
| Host      | User | Password         |
+-----------+------+------------------+
| localhost | root | 1e3392c069a69a58 |
+-----------+------+------------------+
1 row in set (0.00 sec)