php - Docker MYSQL '[2002] Connection refused'

Question

I was trying out Docker for the first time. Got a LEMP stack up and running, but I can't connect to the MYSQL Database. Not on my Symfony application, not on PHPMyAdmin. The applications are returning the following error code:

An exception occured in driver: SQLSTATE[HY000] [2002] Connection refused

This is my docker-compose.yml:

nginx:
    image: tutum/nginx
    ports:
        - "80:80"
    links:
        - phpfpm
    volumes:
        - ./nginx/default:/etc/nginx/sites-available/default
        - ./nginx/default:/etc/nginx/sites-enabled/default

        - ./logs/nginx-error.log:/var/log/nginx/error.log
        - ./logs/nginx-access.log:/var/log/nginx/access.log
phpfpm:
    build: phpfpm/
    ports:
        - "9000:9000"
    volumes:
        - ./public:/usr/share/nginx/html
mysql:
  image: mariadb
  ports:
    - 3306:3306
  environment:
    MYSQL_ROOT_PASSWORD: admin
phpmyadmin:
  image: phpmyadmin/phpmyadmin
  restart: always
  links:
    - mysql
  ports:
    - 8183:80
  environment:
    MYSQL_USERNAME: admin
    MYSQL_ROOT_PASSWORD: admin
    PMA_ARBITRARY: 1

Dockerfile PHPFPM:

    FROM php:fpm

RUN docker-php-ext-enable opcache
RUN apt-get update 
  && apt-get install -y --no-install-recommends libpq-dev 
  && docker-php-ext-install mysqli pdo_pgsql pdo_mysql

GitHub URL: https://github.com/MolengraafFrank/DockerSymfony

Could someone help me out? Thank you for your time.

Answer 1

The '[2002] Connection refused' means you can reach the database server, but you don't have right access for the user (in your case admin). By default mariadb have a root user with the password given by MYSQL_ROOT_PASSWORD and this user can connect from any server (%).

If you want use an over login to your databases, you have to create it in the databases server with the right granting on databases from chosen locations.

The problem here is that you have named your database server as 'mysql' (service name in the docker-compose file). But by default phpmyadmin tries to connect to a database server named 'db'. Adding PMA_HOST: mysql under the environment section of the phpmyadmin service will resolve this problem.

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I think that MYSQL_USERNAME and PMA_ARBITRARY are useless if you work with default configuration (connection with root to your databases server)