To install MariaDB, run the command below;

 # apt-get install mariadb-server mariadb-client

When installed, MariaDB is started and enabled to run on system boot.

 # systemctl is-enabled mariadb
 enabled   
 # systemctl status mariadb
 
 ● mariadb.service - MariaDB 10.3.15 database server
    Loaded: loaded (/lib/systemd/system/mariadb.service; enabled; vendor preset: enabled)
    Active: active (running) since Thu 2019-07-18 15:31:35 EDT; 9min ago
      Docs: man:mysqld(8)
            https://mariadb.com/kb/en/library/systemd/
  Main PID: 2356 (mysqld)
    Status: "Taking your SQL requests now..."
     Tasks: 31 (limit: 1150)
    Memory: 76.4M
    CGroup: /system.slice/mariadb.service
            └─2356 /usr/sbin/mysqld

After installing MariaDB database server, the commands below can be used to stop, start and enable MariaDB service to always start up when the server boots.

  # systemctl stop mariadb.service
  # systemctl start mariadb.service
  # systemctl enable mariadb.service

Database is located at:

  # cd /var/lib/mysql/

The location of the used config file can be found by:

 /usr/sbin/mysqld --verbose --help | grep -A 1 "Default options"

By default, MariaDB uses unix_socket plugin for authentication and thus, it doesn’t require password to login. You can simply run mysql or mysql -u root to login to MariaDB server.

 # mysql

 Welcome to the MariaDB monitor.  Commands end with ; or \g.
 Your MariaDB connection id is 48
 Server version: 10.3.15-MariaDB-1 Debian 10
 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)]>

You can now run the mysql_secure_installation script to remove MariaDB test databases, anonymous users and disallow remote root login. To run the script, just run the command below

 # mysql_secure_installation

When prompted, answer the questions below by following the guide.

Enter current password for root (enter for none): Just press the Enter

• Set root password? [Y/n]: Y
• New password: Enter password
• Re-enter new password: Repeat password
• Remove anonymous users? [Y/n]: Y
• Disallow root login remotely? [Y/n]: Y
• Remove test database and access to it? [Y/n]: Y
• Reload privilege tables now? [Y/n]: Y
• Restart MariaDB server

To test if MariaDB is installed, type the commands below to logon to MariaDB server

  # sudo mysql -u root -p

Then type the password you created above to sign on… if successful, you should see MariaDB welcome message

By default the remote access is disabled. In order to enable remote access make the following changes to the configuration file:

# nano /etc/mysql/mariadb.conf.d/50-server.cnf

Disabled the line: bind-address = 127.0.0.1. 
#bind-address            = 127.0.0.1

#And add 2 new lines:
skip-networking=0
skip-bind-address