About

The mysql-backup Docker image will provide you a container to backup and restore a MySQL or MariaDB database container.

The backup is made with mydumper, a fast MySQL backup utility.

Usage

To backup a MySQL or MariaDB container you simply have to run a container from this Docker image and link a MySQL or MariaDB container to it.

The container will automatically detect the linked database container and tries to backup the database based on the environment variables of the database container:

• <CONTAINER>_ENV_MYSQL_DATABASE
• <CONTAINER>_ENV_MYSQL_ROOT_PASSWORD

Please note the backup will be written to /backup by default, so you might want to mount that directory from your host.

Example Docker CLI client

To create a backup from a MySQL container via docker CLI client:

docker run --name my-backup --link my-mysql -v /var/mysql_backups:/backup confirm/mysql-backup

The container will stop automatically as soon as the backup has finished. To create more backups in the future simply start your container again:

docker start my-backup

To restore a backup into a MySQL container via docker CLI client:

docker run --name my-restore --link my-mysql -v /var/mysql_backups:/backup confirm/mysql-backup

Example Docker Compose

Here's an example of a Docker Compose file, e.g. docker-compose.yml:

backup:
    image: confirm/mysql-backup
    volumes:
        - ./data/backup:/backup
    links:
        - my-mysql
    restart: "no"

Configuration

Mode

By default the container backups the database. However, you can change the mode of the container by setting the following environment variable:

• MODE: Sets the mode of the backup container while [BACKUP|RESTORE]

Base directory

By default the base directory /backup is used. However, you can overwrite that by setting the following environment variable:

• BASE_DIR: Path of the base directory (aka working directory)

Restory directory

By default the container will automatically restore the latest backup found in BASE_DIR. However, you can manually set the name of a backup directory underneath BASE_DIR:

• RESTORE_DIR: Name of a backup directory to restore

This option is only required when the container runs in in RESTORE mode.

UID and GID

By default the backup will be written with UID and GID 666. However, you can overwrite that by setting the following environment variables:

• BACKUP_UID: UID of the backup
• BACKUP_GID: GID of the backup

umask

By default a umask of 0022 will be used. However, you can overwrite that by setting the following environment variable:

• UMASK: Umask which should be used to write the backup files

mydumper / myloader CLI options

By default mydumper is invoked with the -c (compress backup) and myloader with the -o (overwrite tables) CLI option. However, you can modify the CLI options by setting the following environment variable:

• OPTIONS: Options passed to mydumper (when MODE is BACKUP) or myloader (when MODE is RESTORE)