MariaDB is the successor to MySQL after Oracle went a bit crazy on it. MariaDB is more updated, more secure and generally the logical successor to MySQL. And it's 100% compatible.
Installing MariaDB is easy:
emerge mariadb
The Gentoo guide says it all, but i want to ensure that the database is actually stored on the RAID array and not on the Gentoo root folder.
This is configured in /etc/mysql/mariadb.d/50-distro-server.cnf, find and change the following line:
datadir = /data/mysql
move the folder to somewhere under /data/.
After editing this file, run the first time configuration, so before starting it, run:
emerge --config dev-db/mariadb
Input and remember your root password!
Start the service and set it on boot:
rc-update add mysql default /etc/init.d/mysql start
It's a good idea to create a separated database and user for each service you are oging to use with MariaDB. These instructions are not exaustive but only a quick reference:
Login to the MariaDB
mysql -u root -p -h localhost
Creating a database with user
create database DATABASE_NAME; grant all privileges on DATABASE_NAME.* TO 'USER_NAME'@'localhost' identified by 'PASSWORD'; flush privileges;