Clusterable, auto-discoverable MariaDB galera cluster - made for Docker Cloud

Built with the useful topic from Withblue.ink.

Goal of this project is to create an easily deployable MariaDB cluster, that can scale up and down without configuration/setup assle. It uses HOSTNAME (or DOCKERCLOUD_CONTAINER_HOSTNAME on Docker Cloud) env vars to discover other hosts (mariadb-1, mariadb-2, mariadb-3, etc.). Container named with {name}-1 will be the galera cluster creator.

The container is ready to use with Docker Cloud.

mariadb-production:
  environment:
    - MYSQL_ROOT_PASSWORD=password
  image: 'dialonce/mariadb-galera:latest'
  ports:
    - '3306:3306'
  volumes:
    - '/data/mysql:/data'

Then it should automatically grow as you scale it up.

docker build -t dialonce/mariadb-galera:latest .
docker run -it -e MYSQL_ROOT_PASSWORD=root --name=mariadb-1 -e HOSTNAME=mariadb-1 --rm -p 3306:3306 dialonce/mariadb-galera:latest
docker run -it -e MYSQL_ALLOW_EMPTY_PASSWORD=true --name=mariadb-2 -e HOSTNAME=mariadb-2 --rm --link mariadb-1:mariadb-1 dialonce/mariadb-galera:latest

Never shut down the whole cluster - if you do so the nodes may not be able to recover. If for some reason you need to shut down the whole cluster and restart it later, make sure to delete the file named clustered located in shared volume of the first container ({name}-1).

Always set up a rolling deployment process to avoid any clustering shutdown in case of an update.

Creating a MariaDB Galera cluster behind a reverse proxy, that will load balancer and filter incoming requests based on source IP address:

mariadb-production:
  environment:
    - 'EXCLUDE_PORTS=4567,4568,4444'
    - 'EXTRA_SETTINGS=acl network_allowed src 192.168.1.0,block if !network_allowed'
    - MYSQL_ROOT_PASSWORD=password
    - TCP_PORTS=3306
  image: 'dialonce/mariadb-galera:latest'
  sequential_deployment: true
  volumes:
    - '/data/mysql:/data'
mariadb-production-lb:
  environment:
    - 'STATS_AUTH=user:pass'
    - STATS_PORT=1936
  image: 'dockercloud/haproxy:latest'
  links:
    - mariadb-production
  ports:
    - '1936:1936'
    - '3306:3306'
  roles:
    - global