Installing MariaDB on CentOS 8

MariaDB is a fork of the popular cross-platform MySQL database management system and is considered a full drop-in replacement for MySQL. MariaDB was created by one of MySQL’s original developers in 2009 after MySQL was acquired by Oracle during the Sun Microsystems merger. Today MariaDB is maintained and developed by the MariaDB Foundation and community contributors with the intention of it remaining GNU GPL software.

MariaDB replaced MySQL as the default database system in the CentOS 8 repositories. Though installing MySQL into CentOS 8 is not particularly difficult, if you need a database, MariaDB is recommended for official support and a minimal chance of incompatibilities with other repository software.

Before You Begin

1. If you have not already done so, create a Linode account and Compute Instance. See our Getting Started with Linode and Creating a Compute Instance guides.

2. Follow our Setting Up and Securing a Compute Instance guide to update your system and configure your hostname. You may also wish to set the timezone, create a limited user account, and harden SSH access.

   To check your hostname run:

   hostname
   hostname -f
   

   The first command should show your short hostname, and the second should show your fully qualified domain name (FQDN) if you have one assigned.

Install and Setup MariaDB

Install MariaDB using the package manager.

sudo yum install mariadb-server

Enable MariaDB to start on boot and then start the service:

sudo systemctl enable mariadb
sudo systemctl start mariadb

MariaDB will bind to localhost (127.0.0.1) by default. For information on connecting to a remote database using SSH, see our MySQL remote access guide, which also applies to MariaDB.

Securing the Installation

1. Run the mysql_secure_installation script to address several security concerns in a default MariaDB installation:

   sudo mysql_secure_installation
   

You will be given the choice to change the MariaDB root password, remove anonymous user accounts, disable root logins outside of localhost, and remove test databases. It is recommended that you answer yes to these options. You can read more about the script in the MariaDB Knowledge Base.

MariaDB Client

The standard tool for interacting with MariaDB is the mariadb client, which installs with the mariadb-server package. The MariaDB client is used through a terminal using the mysql command.

Root Login

1. Log into MariaDB as the root user:

   sudo mysql -u root -p
   

2. When prompted, enter the root password you assigned when the mysql_secure_installation script was run.

   You’ll then be presented with a welcome header and the MariaDB prompt as shown below:

   MariaDB [(none)]>

3. To generate a list of commands for the MariaDB prompt, enter \h. You’ll then see:

   General information about MariaDB can be found at
   http://mariadb.org
   
   List of all MySQL commands:
   Note that all text commands must be first on line and end with ';'
   ?         (\?) Synonym for `help'.
   clear     (\c) Clear the current input statement.
   connect   (\r) Reconnect to the server. Optional arguments are db and host.
   delimiter (\d) Set statement delimiter.
   edit      (\e) Edit command with $EDITOR.
   ego       (\G) Send command to mysql server, display result vertically.
   exit      (\q) Exit mysql. Same as quit.
   go        (\g) Send command to mysql server.
   help      (\h) Display this help.
   nopager   (\n) Disable pager, print to stdout.
   notee     (\t) Don't write into outfile.
   pager     (\P) Set PAGER [to_pager]. Print the query results via PAGER.
   print     (\p) Print current command.
   prompt    (\R) Change your mysql prompt.
   quit      (\q) Quit mysql.
   rehash    (\#) Rebuild completion hash.
   source    (\.) Execute an SQL script file. Takes a file name as an argument.
   status    (\s) Get status information from the server.
   system    (\!) Execute a system shell command.
   tee       (\T) Set outfile [to_outfile]. Append everything into given outfile.
   use       (\u) Use another database. Takes database name as argument.
   charset   (\C) Switch to another charset. Might be needed for processing binlog with multi-byte charsets.
   warnings  (\W) Show warnings after every statement.
   nowarning (\w) Don't show warnings after every statement.
   
   For server side help, type 'help contents'
   
   MariaDB [(none)]>

Using MariaDB

Create a New MariaDB User and Database

1. If you’re not already logged in, log into the database again. This time, if you set a password above, enter it at the prompt.

   sudo mysql -u root -p
   

2. In the example below, testdb is the name of the database, testuser is the user, and password is the user’s password. You should replace password with a secure password:

    CREATE DATABASE testdb;
    CREATE user 'testuser'@localhost IDENTIFIED BY 'password';
    GRANT ALL ON testdb.* TO 'testuser' IDENTIFIED BY 'password';
   

   You can shorten this process by creating the user while assigning database permissions:

    CREATE DATABASE testdb;
    GRANT ALL ON testdb.* TO 'testuser' IDENTIFIED BY 'password';
   

3. Then exit MariaDB:

   exit;
   

Create a Sample Table

1. Log back in as testuser:

   sudo mysql -u testuser -p
   

2. Create a sample table called customers:

   USE testdb;
   CREATE TABLE customers (customer_id INT NOT NULL AUTO_INCREMENT PRIMARY KEY, first_name TEXT, last_name TEXT);
   

   • This creates a table with a customer_id field of the type INT for integer.
     • This field is auto-incremented for new records and used as the primary key.
   • Two other fields are created, first_name and last_name for storing the customer’s name.

3. View the new table:

   SHOW TABLES;
   

   +------------------+
   | Tables_in_testdb |
   +------------------+
   | customers        |
   +------------------+
   1 row in set (0.00 sec)

4. Add some data:

   INSERT INTO customers (first_name, last_name) VALUES ('John', 'Doe');
   

5. View the data:

   SELECT * FROM customers;
   

   +-------------+------------+-----------+
   | customer_id | first_name | last_name |
   +-------------+------------+-----------+
   |           1 | John       | Doe       |
   +-------------+------------+-----------+
   1 row in set (0.00 sec)

6. Then exit MariaDB:

   exit;
   

Reset the MariaDB Root Password

If you forget your root MariaDB password, it can be reset.

1. Stop the current MariaDB server instance.

   sudo systemctl stop mariadb
   

2. Then execute the following command which will allow the database to start without loading the grant tables or networking.

   sudo systemctl set-environment MYSQLD_OPTS="--skip-grant-tables --skip-networking"
   

3. Restart MariaDB:

   sudo systemctl start mariadb
   

4. Login to the MariaDB server with the root account, this time without supplying a password:

   sudo mysql -u root
   

5. Use the following commands to reset root’s password. Replace password with a strong password:

   FLUSH PRIVILEGES;
   UPDATE mysql.user SET password = PASSWORD('password') WHERE user = 'root';
   

6. Update the authentication methods for the root password:

   UPDATE mysql.user SET authentication_string = '' WHERE user = 'root';
   UPDATE mysql.user SET plugin = '' WHERE user = 'root';
   exit;
   

7. Revert the environment settings to allow the database to start with grant tables and networking:

   sudo systemctl unset-environment MYSQLD_OPTS
   

8. Then restart MariaDB:

   sudo systemctl start mariadb
   

9. You should now be able to log into the database with your new root password:

   sudo mysql -u root -p
   

More Information

You may wish to consult the following resources for additional information on this topic. While these are provided in the hope that they will be useful, please note that we cannot vouch for the accuracy or timeliness of externally hosted materials.

• MariaDB Knowledge Base
• MariaDB FAQ
• MariaDB SQL commands