Docker MYSQL '[2006] MySQL server has gone away'

问题

i have a little problem with mysql server. i created my docker-compose.yml, but when i want to access to phpMyAdmin (localhost:8080), an error message appeared sais that: "phpMyAdmin tried to connect to the MySQL server, and the server rejected the connection. Please check the values of host, username and password in the configuration and make sure they match the information provided by the MySQL server administrator".

Here is my docker-compose file and thanks for helping me

version: '2'
services:
  apache:
    image: rafaelcgstz/magento2
    # build: .
    ports:
      - 80:80
      - 9001:9000
      # - "35729:35729" # live reload
    volumes:
      - ./src:/var/www/html
      - ~/.composer:/var/www/.composer
      - ~/.npm:/var/www/.npm
      # - ~/.nvm:/var/www/.nvm
    environment:
      XDEBUG_CONFIG: "remote_host=localhost"
      PHP_IDE_CONFIG: "serverName=Docker"
    depends_on:
      - db
    links:
      - db
    networks:
      - magento-network

  db:
    image: mariadb
    ports:
     - 3300:3306
    environment:
      - MYSQL_ROOT_PASSWORD=root
      - MYSQL_DATABASE=magento
      - MYSQL_USER=magento
      - MYSQL_PASSWORD=magento
    volumes:
      - dbdata:/var/lib/mysql
    networks:
      - magento-network

  phpmyadmin:
    image: phpmyadmin/phpmyadmin
    environment:
     - PMA_HOST=db
     - PMA_USER=root
     - PMA_PASSWORD=root
     - MYSQL_ROOT_PASSWORD=root
    ports:
     - 8080:80
    networks:
      - magento-network

  redis:
    image: redis
    ports:
     - 6379
    networks:
      - magento-network

  redis-session:
    image: redis
    ports:
     - 6379
    networks:
      - magento-network

  mailhog:
    image: mailhog/mailhog
    ports:
      - 1025:1025
      - 8025:8025
    networks:
      - magento-network

networks:
  magento-network:
    driver: bridge

volumes:
  dbdata:
    driver: local

回答1:

Seems like you have a typo in mariadb service definition:

ports:
     - 3300:3306

You configured port mapping so that container is reachable at 3300 but you did not pass this information to PHPMyadmin. As a result connection attempt just times out.

Side note: you do not need to expose port for database at all - other containers will communicate with it using Docker's virtual network and for local access you can use docker container -it exec <container-id> mysql... or docker-compose exec db mysql...

回答2:

while it appears there is a typo for the port with this post I want to point out that it's important to make sure that your user has access 'TO' and 'FROM' the appropriate IP.

This is an (wide open -adjust as needed) example for updating the access domain when running adminer / phpadmin via docker:

GRANT ALL ON . TO 'admin'@'172.18.0.0/255.255.255.0' IDENTIFIED BY 'password' WITH GRANT OPTION;

p.s. I'm adding this answer here because I also landed on this page with the same error.

来源：https://stackoverflow.com/questions/57834108/docker-mysql-2006-mysql-server-has-gone-away

标签

mysql

Docker

phpMyAdmin

docker-compose