Docker MYSQL '[2002] Connection refused'

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.

I had this challenge because I am running 3 different containers with different IP Addresses

db - 172.18.0.3 - container for MYSQLapp - 172.18.0.2 - container for Laravel app

so I fixed it by editing my Laravel .env file

DB_CONNECTION=mysqlDB_HOST=172.18.0.3DB_PORT=3306DB_DATABASE=database_nameDB_USERNAME=username...

To get your containers Ip addresses. From your docker host

docker inspect -f '{{.Name}} - {{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' $(docker ps -aq)

UPDATED:For latest docker versions and based on the services name, "mysql", in your docker-compose.yml

mysql:  image: mariadb  ports:    - 3306:3306

You can try this:

DB_CONNECTION=mysqlDB_HOST=mysqlDB_PORT=3306DB_DATABASE=database_nameDB_USERNAME=username

DB_HOST is the name of MySQL service name defined in docker-compose.yml

I've managed to connect to the mysql instance using mysql command line tool, this is the command I used - mysql -u root -p -h 127.0.0.1, and the entering the admin password. Is that a sufficient solution for you?