docker phppyadmin container Access denied for user 'root' - mysql

Question

I have installed docker on digitalocean droplet successfully and below shows my docker-compose.yml configurations:
version: '2.1'
services:
mysql:
build:
context: ./docker/mysql
image: mysql:latest
ports:
- 3306:3306
environment:
MYSQL_ROOT_PASSWORD: root_pass
MYSQL_USER: root
MYSQL_PASSWORD: root_pass
volumes:
- mysqldata:/var/lib/mysql
phpmyadmin:
image: phpmyadmin/phpmyadmin
container_name: phpmyadmin
links:
- mysql:db
environment:
MYSQL_USERNAME: root
MYSQL_ROOT_PASSWORD: root_pass
restart: always
ports:
- 8080:80
And once I up the docker services everything works fine as you can see by below screen capture.
And I can access my mysql database inside terminal perfectly with my user credentials.
But the problem is when I try to access phpmyadmin with droplet_ip:8080 its says:
#1045 - Access denied for user 'root'#'172.18.0.4' (using password: YES)
And here I used same username (root) password (root_pass) as well.
Any suggestions regarding this problem would be grateful. Thank you.

Answer 1

The following works for me
version: '3.1'
volumes:
mysql-volume:
services:
mysql:
image: mysql
container_name: mysql
volumes:
- mysql-volume:/var/lib/mysql
environment:
MYSQL_ROOT_PASSWORD: rootpass
MYSQL_DATABASE: db
MYSQL_USER: user
MYSQL_PASSWORD: supersecret
phpmyadmin:
image: phpmyadmin/phpmyadmin
container_name: phpmyadmin
environment:
PMA_HOST: mysql
MYSQL_USER: user
MYSQL_PASSWORD: supersecret
ports:
- 80:80
depends_on:
- mysql
don't mix up root user and MySQL user. In my example above I use the MySQL user to login with phpadmin. if you want to login using your root user you don't have to specify MySQL user and it will look like this (you don't need to specify a user for phpmyadmin because it's always root):
version: '3.1'
volumes:
mysql-volume:
services:
mysql:
image: mysql
container_name: mysql
volumes:
- mysql-volume:/var/lib/mysql
environment:
MYSQL_ROOT_PASSWORD: rootpass
MYSQL_DATABASE: db
phpmyadmin:
image: phpmyadmin/phpmyadmin
container_name: phpmyadmin
environment:
PMA_HOST: mysql
MYSQL_ROOT_PASSWORD: rootpass
ports:
- 80:80
depends_on:
- mysql
Also very important, remove your mysql volume when you want to recreate the whole setup. (docker volume rm ..). Because maybe your mysql is started with the same volume again after making changes.

Answer 2

I got the access denied error because I had a dollar sign in my password, which the docker compose file parses as variable substitution (I've only seen the ${} syntax) on this page you will read "Both $VARIABLE and ${VARIABLE} syntax are supported."
Therefore if I had for example this as my database password in the docker compose file: hello$world, the world variable would get substituted, of course I don't have a 'world' variable, the password that would be set in that case would be hello, so without knowing the docker compose syntax you would be trying to log in with hello$world, and you'd be denied access.