version: "3.3" services: backend: image: nanoserver/mysql environment: MYSQL_USER: root MYSQL_PASSWORD: Password123 ports: - mode: host target: 3306 published: 3306 networks: - collabnet deploy: endpoint_mode: dnsrr placement: constraints: - 'node.platform.os == windows' frontend: depends_on: - backend image: wordpress:latest environment: WORDPRESS_DB_HOST: backend:3306 WORDPRESS_DB_USER: root WORDPRESS_DB_PASSWORD: Password123 ports: - mode: host target: 80 published: 80 networks: - collabnet deploy: endpoint_mode: dnsrr placement: constraints: - 'node.platform.os == linux' networks: collabnet: