Docker Compose phpmyadmin not connecting to MySQL - mysql

Question

I have a docker compose file which is basically trying to build a WAMP/LAMP style environment.
Basically, PHPMyAdmin can't seem to connect to MySQL. Looking through answers here, it appeared that it was an issue with legacy auth using MySQL Image 8 so I added:
command: --default-authentication-plugin=mysql_native_password
but that didn't work, so I dropped down to mysql image5.7 and the issue is still present. For some reason, I can't connect to MySQL and I get the error:
mysqli_real_connect(): php_network_getaddresses: getaddrinfo failed: Try again
and
mysqli_real_connect(): (HY000/2002): php_network_getaddresses: getaddrinfo failed: Try again
Here is a copy of my Docker Compose which I don't think is doing anything weird.
Hoping someone can clarify that for me.
version: "3.1"
services:
site:
build: .
ports :
- "80:80"
volumes:
- ./www:/var/www/html/
links:
- database
networks:
- php-network
#######################################
# PHP MY ADMIN
#######################################
phpmyadmin:
build:
context: .
dockerfile: PHPMYADMIN.Dockerfile
restart: always
links:
- database:mysql
environment:
PMA_HOST: mysql
PMA_PORT: 3306
ports:
- "8080:80"
environment:
- MYSQL_USERNAME=admin
- MYSQL_PASSWORD=root
networks:
- php-network
#######################################
# MySQL server
#######################################
database:
image: mysql:5.7.25
ports:
- "3306:3306"
container_name: db-mysql
restart: always
environment:
- MYSQL_ROOT_PASSWORD=root
- MYSQL_DATABASE=test_db
- MYSQL_USER=admin
- MYSQL_PASSWORD=root
networks:
- php-network
networks:
php-network:
driver: bridge
I also saw mention of a "depends on" flag which I tried too but that also failed to allow me to connect. I have had the same error throughout.

Answer 1

It's about the container name.
database:
image: mysql:5.7.25
ports:
- "3306:3306"
- **container_name: db-mysql**
and in your phpcontainer:
phpmyadmin:
build:
context: .
dockerfile: PHPMYADMIN.Dockerfile
restart: always
links:
- database:mysql
environment:
**PMA_HOST: mysql**
PMA_PORT: 3306
you define host as mysql, which in docker network will be unrecognizable.
try switching PMA_HOST to db-mysql.
Sorry for bad formatting.
Also use docker ps to see docker container names and to figure out which hosts do you need to connect.

Answer 2

I've got this working now with the following:
version: "3.1"
services:
www:
build: .
ports:
- "8081:80"
volumes:
- ./www:/var/www/html/
links:
- db
networks:
- default
#######################################
# MySQL server
#######################################
db:
image: mysql:5.7.25
ports:
- "3306:3306"
environment:
MYSQL_DATABASE: test_db
MYSQL_ROOT_PASSWORD: test
volumes:
- ./dump:/docker-entrypoint-initdb.d
- persistent:/var/lib/mysql
networks:
- default
#######################################
# PHP MY ADMIN
#######################################
phpmyadmin:
image: phpmyadmin/phpmyadmin
links:
- db:db
ports:
- 8080:80
environment:
MYSQL_USER: user
MYSQL_PASSWORD: test
MYSQL_ROOT_PASSWORD: test
volumes:
persistent:

Answer 3

According to your phpmyadmin service configuration, you are trying to reach mysql container by mysql address:
environment:
PMA_HOST: mysql
PMA_PORT: 3306
But container with mysql server is accessible by database or db-mysql addresses.
So, you need to change phpmyadmin service configuration to:
environment:
PMA_HOST: database
PMA_PORT: 3306