[Docker]: Connecting PHPMyAdmin to MySQL doesnt work

The configuration file of phpmyadmin/phpmyadmin (/www/config.inc.php) say by default the host name of database server if 'db' :

$hosts = array('db');

So if your database name container is not 'db', you should add the environment variable PMA_HOST= (or PMA_HOSTS if multi db servers) with the right name (databaseContainer in your case)

docker run --name db -e MYSQL_ROOT_PASSWORD=mypass -d mysql:5.7 docker run -p 80:80 --link db:mysql phpmyadmin/phpmyadmin 

Try executing the above command it will work, as phpmyadmin may have hardcoded the in their implementation that the mysql server conatiner name to be db.

If you still want to give your db server a unique name, add PMA_HOST environment variable:

docker run --name myadmin -d --link mysqlserver:mysql -p 8080:80 -e PMA_HOST=mysqlserver phpmyadmin/phpmyadmin 

mysqlserver is the name give to your mysql db server.

GIVEN you started the MySQL container as:

$ docker run --name databaseContainer -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql

THEN you should actually create phpmyadmin as follows:

$ docker run --name myadmin -d --link mysql:db -p 8080:8080 phpmyadmin/phpmyadmin

It is actually advisable that you include a network. So you would have:

$ docker run --name databaseContainer --network myDockerNetwork -e MYSQL_ROOT_PASSWORD=my-secret-pw -d mysql

AND

$ docker run --name myadmin -d --link mysql:db --network myDockerNetwork -p 8080:8080 phpmyadmin/phpmyadmin

Make sure your network is created first:

$ docker network create myDockerNetwork

In my case, I was using MySQL 8.0 and it turned out that mysql has introduced a new password identification which is not supported by phpmyadmin. See this answer.

I've had the same error installing docker using laradock, then running docker-compose up. Out of the box, default config throws this error when you attempt to log into phpMyAdmin (using current images as of Oct 2018). The error was not present using docker run.

For docker-compose.yml (version 3), one cause is services running on different networks by default. For anyone else having this issue, here is a config that works for mysql and phpmyadmin.

Inside "docker-compose.yml" file, under "services":

### db ################################################### db: image: mysql:5.7 container_name: db environment: - MYSQL_ROOT_PASSWORD=mypass networks: - backend ### MySQL ################################################ mysql: build: context: ./mysql args: - MYSQL_VERSION=${MYSQL_VERSION} environment: - MYSQL_DATABASE=${MYSQL_DATABASE} - MYSQL_USER=${MYSQL_USER} - MYSQL_PASSWORD=${MYSQL_PASSWORD} - MYSQL_ROOT_PASSWORD=${MYSQL_ROOT_PASSWORD} - TZ=${WORKSPACE_TIMEZONE} volumes: - ${DATA_PATH_HOST}/mysql:/var/lib/mysql - ${MYSQL_ENTRYPOINT_INITDB}:/docker-entrypoint-initdb.d ports: - "${MYSQL_PORT}:3306" networks: - backend ## phpMyAdmin ########################################### phpmyadmin: build: ./phpmyadmin environment: - PMA_ARBITRARY=1 - PMA_HOST=db - MYSQL_USER=${PMA_USER} - MYSQL_PASSWORD=${PMA_PASSWORD} - MYSQL_ROOT_PASSWORD=${PMA_ROOT_PASSWORD} ports: - "${PMA_PORT}:80" depends_on: - db - mysql networks: - frontend - backend 

Edit the ".env" file as follows:

### MYSQL ################################################# MYSQL_VERSION=5.7 MYSQL_DATABASE=db MYSQL_USER=root MYSQL_PASSWORD=mypass MYSQL_PORT=3306 MYSQL_ROOT_PASSWORD=mypass MYSQL_ENTRYPOINT_INITDB=./mysql/docker-entrypoint-initdb.d ### PHP MY ADMIN ########################################## # Accepted values: mariadb - mysql PMA_DB_ENGINE=mysql # Credentials/Port: PMA_USER=default PMA_PASSWORD=secret PMA_ROOT_PASSWORD=secret PMA_PORT=8080 

Add the following line to the "/etc/hosts" file:

127.0.0.1 localhost 

Assuming you're also using nginx, and that config is elsewhere in your "docker-compose.yml", you can build and start these services with:

docker-compose up -d mysql nginx db phpmyadmin 

Then navigate to localhost:8080 in your browser and login with username "root" and password "mypass" (leave server field blank).