Change root password in MariaDB Docker container running with docker compose

Override the entrypoint in docker compose.yml for the MariaDB Docker container by adding:

entrypoint: mysqld_safe –skip-grant-tables –user=mysql

The start up the Docker Compose stack:

$> docker compose up -d

Then login to the Docker container:

$> sudo docker exec -ti docker-container-name bash

And login as root without password:

$> mysql -u root -p

Change the root password in mysql cli:

mysql> FLUSH PRIVILEGES;
mysql> ALTER USER ‘root’@’localhost’ IDENTIFIED BY ‘new_password’;
mysql> FLUSH PRIVILEGES;

Logout of mysql and the Docker container (2x exit), remove the entrypoint line from the docker compose.yml and reload the Docker Composer stack:

$> docker compose up -d

You can now login to the MariaDB container and connect to the database with the new root password:

$> sudo docker exec -ti docker-container-name bash
$> mysql -u root -p