MySQL 8.0 SQL Database Server container image

This container image includes MySQL 8.0 SQL database server for general usage. Users can choose between RHEL8 and RockyLinux8 based images.

Description

This container image provides a containerized packaging of the MySQL mysqld daemon and client application. The mysqld server daemon accepts connections from clients and provides access to content from MySQL databases on behalf of the clients.

Usage

If you want to set only the mandatory environment variables and not store the database in a host directory, execute the following command:

$ podman run -d --name mysql_database -e MYSQL_USER=user -e MYSQL_PASSWORD=pass -e MYSQL_DATABASE=db -p 3306:3306 (Image:tag)

This will create a container named mysql_database running MySQL with database db and user with credentials user:pass. Port 3306 will be exposed and mapped to the host. If you want your database to be persistent across container executions, also add a -v /host/db/path:/var/lib/mysql/data argument. This will be the MySQL data directory.

If the database directory is not initialized, the entrypoint script will first run mysql_install_db and setup necessary database users and passwords. After the database is initialized, or if it was already present, mysqld is executed and will run as PID 1. You can stop the detached container by running podman stop mysql_database.

Environment variables and volumes

The image recognizes the following environment variables that you can set during initialization by passing -e VAR=VALUE to the Docker run command.

MYSQL_USER
User name for MySQL account to be created

MYSQL_PASSWORD
Password for the user account

MYSQL_DATABASE
Database name

MYSQL_ROOT_PASSWORD
Password for the root user (optional)

You can also set the following mount points by passing the -v /host:/container flag to Docker.

/var/lib/mysql/data
MySQL data directory

Notice: When mouting a directory from the host into the container, ensure that the mounted directory has the appropriate permissions and that the owner and group of the directory matches the user UID or name which is running inside the container.

MySQL auto-tuning

When the MySQL image is run with the --memory parameter set and you didn't specify value for some parameters, their values will be automatically calculated based on the available memory.

MYSQL_KEY_BUFFER_SIZE (default: 10%)
key_buffer_size

MYSQL_READ_BUFFER_SIZE (default: 5%)
read_buffer_size

MYSQL_INNODB_BUFFER_POOL_SIZE (default: 50%)
innodb_buffer_pool_size

MYSQL_INNODB_LOG_FILE_SIZE (default: 15%)
innodb_log_file_size

MYSQL_INNODB_LOG_BUFFER_SIZE (default: 15%)
innodb_log_buffer_size

MySQL root user

The root user has no password set by default, only allowing local connections. You can set it by setting the MYSQL_ROOT_PASSWORD environment variable. This will allow you to login to the root account remotely. Local connections will still not require a password.

To disable remote root access, simply unset MYSQL_ROOT_PASSWORD and restart the container.

Changing passwords

Since passwords are part of the image configuration, the only supported method to change passwords for the database user (MYSQL_USER) and root user is by changing the environment variables MYSQL_PASSWORD and MYSQL_ROOT_PASSWORD, respectively.

Changing database passwords through SQL statements or any way other than through the environment variables aforementioned will cause a mismatch between the values stored in the variables and the actual passwords. Whenever a database container starts it will reset the passwords to the values stored in the environment variables.