The Debian packages available from mariadb.org are not identical to the official Debian packages available from Debian's own repositories. The mariadb.org packages are generated using the Debian packaging in the main tree debian/ directory: https://github.com/MariaDB/server/tree/10.1/debian. The Debian packages in official Debian (and Ubuntu) however are generated from https://anonscm.debian.org/cgit/pkg-mysql/mariadb-10.1.git/tree/debian.
MariaDB when installed from the Debian repos has a number of differences with standard MariaDB.
Configuration file locations
The file /etc/mysql/my.cnf is handled by the mysql-common update-alternatives mechanism and points to mysql.cnf or mariadb.cnf depending on which one is installed. Most of the MariaDB config files are therefore actually in /etc/mysql/mariadb.d/*.cnf
|Variable||MariaDB in Debian||Standard MariaDB||Notes|
|character_set_server||utf8mb4||latin1||Debian sets a default character set that can support emojis etc.|
|Option||MariaDB in Debian||Standard MariaDB||Notes|
|plugin-load-add||auth_socket.so||-||Debian enables the UNIX_SOCKET Authentication Plugin plugin by default, allowing passwordless login.|
For details, check out the Debian and Ubuntu official repositories: