yum -y install mariadb mariadb-server

[root@centos001 ~]# systemctl start mariadb
[root@centos001 ~]# systemctl status mariadb
● mariadb.service - MariaDB database server
   Loaded: loaded (/usr/lib/systemd/system/mariadb.service; disabled; vendor preset: disabled)
   Active: active (running) since Wed 2019-05-08 15:23:10 CST; 14s ago
  Process: 13148 ExecStartPost=/usr/libexec/mariadb-wait-ready $MAINPID (code=exited, status=0/SUCCESS)
  Process: 13069 ExecStartPre=/usr/libexec/mariadb-prepare-db-dir %n (code=exited, status=0/SUCCESS)
 Main PID: 13147 (mysqld_safe)
   CGroup: /system.slice/mariadb.service
           ├─13147 /bin/sh /usr/bin/mysqld_safe --basedir=/usr
           └─13309 /usr/libexec/mysqld --basedir=/usr --datadir=/var/lib/mysql --plugin-dir=/usr/lib64/mysql/plugin --log-error=/var/log/mariadb/mariadb.log --pid-file=/var/run/mariadb/mariadb...

May 08 15:23:08 centos001 mariadb-prepare-db-dir[13069]: MySQL manual for more instructions.
May 08 15:23:08 centos001 mariadb-prepare-db-dir[13069]: Please report any problems at http://mariadb.org/jira
May 08 15:23:08 centos001 mariadb-prepare-db-dir[13069]: The latest information about MariaDB is available at http://mariadb.org/.
May 08 15:23:08 centos001 mariadb-prepare-db-dir[13069]: You can find additional information about the MySQL part at:
May 08 15:23:08 centos001 mariadb-prepare-db-dir[13069]: http://dev.mysql.com
May 08 15:23:08 centos001 mariadb-prepare-db-dir[13069]: Consider joining MariaDB‘s strong and vibrant community:
May 08 15:23:08 centos001 mariadb-prepare-db-dir[13069]: https://mariadb.org/get-involved/
May 08 15:23:08 centos001 mysqld_safe[13147]: 190508 15:23:08 mysqld_safe Logging to ‘/var/log/mariadb/mariadb.log‘.
May 08 15:23:08 centos001 mysqld_safe[13147]: 190508 15:23:08 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
May 08 15:23:10 centos001 systemd[1]: Started MariaDB database server.
[root@centos001 ~]#

[root@centos001 ~]# systemctl enable mariadb
Created symlink from /etc/systemd/system/multi-user.target.wants/mariadb.service to /usr/lib/systemd/system/mariadb.service.

[root@centos001 ~]# mysql_secure_installation

NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB
SERVERS IN PRODUCTION USE! PLEASE READ EACH STEP CAREFULLY!

In order to log into MariaDB to secure it, we‘ll need the current
password for the root user. If you‘ve just installed MariaDB, and
you haven‘t set the root password yet, the password will be blank,
so you should just press enter here.

Enter current password for root (enter for none):
OK, successfully used password, moving on...

Setting the root password ensures that nobody can log into the MariaDB
root user without the proper authorisation.

Set root password? [Y/n] ^[[A^H^H^H
Set root password? [Y/n] y
New password:
Re-enter new password:
Password updated successfully!
Reloading privilege tables..
... Success!

By default, a MariaDB installation has an anonymous user, allowing anyone
to log into MariaDB without having to have a user account created for
them. This is intended only for testing, and to make the installation
go a bit smoother. You should remove them before moving into a
production environment.

Remove anonymous users? [Y/n] y
... Success!

Normally, root should only be allowed to connect from ‘localhost‘. This
ensures that someone cannot guess at the root password from the network.

Disallow root login remotely? [Y/n] n
... skipping.

By default, MariaDB comes with a database named ‘test‘ that anyone can
access. This is also intended only for testing, and should be removed
before moving into a production environment.

Remove test database and access to it? [Y/n] n
... skipping.

Reloading the privilege tables will ensure that all changes made so far
will take effect immediately.

Reload privilege tables now? [Y/n] y
... Success!

Cleaning up...

All done! If you‘ve completed all of the above steps, your MariaDB
installation should now be secure.

Thanks for using MariaDB!
[root@centos001 ~]#

[root@centos001 ~]# mysql -u root -p
Enter password:
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 13
Server version: 5.5.60-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.

MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| test |
+--------------------+
4 rows in set (0.00 sec)

MariaDB [(none)]>

[root@centos001 ~]#  rpm -qa | grep mariadb
mariadb-libs-5.5.60-1.el7_5.x86_64
mariadb-5.5.60-1.el7_5.x86_64
mariadb-server-5.5.60-1.el7_5.x86_64

vi /etc/my.cnf