Installing mariadb and setting up Database access is straight forward. Redhat 7 or Centos 7 provides mariaDB packages as a replacement for MySQL.

Since mariaDB packages does not come installed by default, it needs to be installed. You may also choose to install from a mariaDB repository, by adding the repository meta data from the official mariaDB repository page by choosing the correct distribution and the required version of mariaDB. The below repository data is added to /etc/yum.repos.d/mariadb.repo

# MariaDB 10.3 RedHat repository list - created 2018-09-03 06:47 UTC
# http://downloads.mariadb.org/mariadb/repositories/
[mariadb]
name = MariaDB
baseurl = http://yum.mariadb.org/10.3/rhel7-amd64
gpgkey=https://yum.mariadb.org/RPM-GPG-KEY-MariaDB
gpgcheck=1

Install mariadb packages

[root@unixutils ~]# yum install -y mariadb mariadb-server mariadb-client

start and enable mariaDB packages

[root@unixutils ~]# systemctl start mariadb && systemctl enable mariadb
[root@unixutils ~]# systemctl status mariadb

Whitlist mysql service in firewall.

[root@unixutils ~]# firewall-cmd --permanent --add-service=mysql 
[root@unixutils ~]# firewall-cmd --reload

In order to harden or secure the mariadb installation, we need to run the ‘mysql_secure_installation’ binary.

[root@unixutils ~]# 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] 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] y
 ... Success!

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] y
 - Dropping test database...
 ... Success!
 - Removing privileges on test database...
 ... Success!

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@unixutils ~]# mysql -u root -p

Enter password:
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 11
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.

Creating a Database named “unixutilsdb”

MariaDB [(none)]> CREATE DATABASE `unixutilsdb`;
Query OK, 1 row affected (0.00 sec)

Creating a user ‘admin’ with password

MariaDB [(none)]> CREATE USER 'admin' IDENTIFIED BY 'mypassword';
Query OK, 0 rows affected (0.00 sec)

Allow user ‘admin’ to have full rights on ‘unixutilsdb’ abd allow ‘admin’ to connect from any remote system.

MariaDB [(none)]> GRANT ALL privileges ON `unixutilsdb`.* TO 'admin'@%;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near '%' at line 1
MariaDB [(none)]> GRANT ALL privileges ON `unixutilsdb`.* TO 'admin'@'%';
Query OK, 0 rows affected (0.00 sec)
MariaDB [(none)]> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

Verify access for user ‘admin’

MariaDB [(none)]> SHOW GRANTS FOR 'admin'@'%';
+------------------------------------------------------------------------------------------------------+
| Grants for admin@%                                                                                   |
+------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'admin'@'%' IDENTIFIED BY PASSWORD '*1083025DF15ADB2C0BB22220464EF1F3C583D362' |
| GRANT ALL PRIVILEGES ON `unixutilsdb`.* TO 'admin'@'%'                                               |
+------------------------------------------------------------------------------------------------------+
2 rows in set (0.01 sec)

MariaDB [(none)]> Bye

User admin should be able to connect to database with the below details from a MySQL client such as HeidiSQL or MySQL Workbench .

Username : admin
password : password
server name : unixutils
Database name : unixutilsdb