docker-compose.yml

version: '3'
services:

  db_master:
    image: jamiejackson/mariadb-replication:10.2
    container_name: db_master
    ports:
      - "3307:3306"
    restart: unless-stopped
    environment:
      #- MYSQL_ALLOW_EMPTY_PASSWORD=1
      - MYSQL_ROOT_PASSWORD=${MYSQL_ROOT_PASSWORD}

  db_slave1:
    image: jamiejackson/mariadb-replication:10.2
    container_name: db_slave1
    depends_on:
      - "db_master"
    ports: 
     - "3308:3306"
    links:
      - db_master:master
    restart: unless-stopped
    environment:
      #- MYSQL_ALLOW_EMPTY_PASSWORD=1
      - MASTER_HOST=master
      - MASTER_PORT=3306
      - MYSQL_ROOT_PASSWORD=${MYSQL_ROOT_PASSWORD}

  db_slave2:
    image: jamiejackson/mariadb-replication:10.2
    container_name: db_slave2
    depends_on:
      - "db_master"
    ports: 
     - "3309:3306"
    links:
      - db_master:master
    restart: unless-stopped
    environment:
      #- MYSQL_ALLOW_EMPTY_PASSWORD=1
      - MASTER_HOST=master
      - MASTER_PORT=3306
      - MYSQL_ROOT_PASSWORD=${MYSQL_ROOT_PASSWORD}