Docker / phpmyadmin: Unable to connecto - mysql

Question

I have the following docker-compose file.
version: "3.7"
services:
main:
container_name: buspack_main
build:
context: .
target: development
volumes:
- .:/usr/src/app
- /usr/src/app/node_modules
ports:
- ${API_PORT}:${API_PORT}
command: bash -c "npm install --save && npm run start:dev"
env_file:
- .env
networks:
- webnet
depends_on:
- db
links:
- db
restart: always
db:
container_name: buspack_db
image: mysql:5.7.33
networks:
- webnet
environment:
MYSQL_ROOT_PASSWORD: 123456
MYSQL_DATABASE: "backendnest"
ports:
- 23306:3306
restart: always
volumes:
- ./db:/var/lib/mysql:rw
phpmyadmin:
container_name: buspack_phpmyadmin
image: phpmyadmin/phpmyadmin
depends_on:
- db
restart: always
ports:
- '8030:80'
environment:
PMA_HOST: buspack_db
MYSQL_ROOT_PASSWORD: 123456
networks:
webnet:
volumes:
db: {}
My problem Is that when I try to login with phpmyadmin I get the following error:
mysqli::real_connect(): php_network_getaddresses: getaddrinfo failed: Temporary failure in name resolution
And also
mysqli::real_connect(): (HY000/2002): php_network_getaddresses: getaddrinfo failed: Temporary failure in name resolution
Is there something I'm missing?

Answer 1

networks:
- webnet
add webnet network to phpmyadmin service

Answer 2

There are more options to solve the connection.
Add phpmyadmin container to webnet network as Def Soudani suggests. The YML example provided overrides the default network. Since the phpMyAdmin is lacking the network config, it won't be on the webnet docker network by default.
Remove all networks related config from the YML. Since compose already creates a default network (docs) for the containers within one YML file.
Use the PMA_ARBITRARY=1 (docs )which allows you to enter a database server hostname on login form.
Example of my YML setup with custom bridge networking:
version: '3.8'
services:
mysql:
image: mysql:5.7
container_name: myapp-mysql-db
restart: unless-stopped
ports:
- "3306:3306"
environment:
MYSQL_DATABASE: ${DB_DATABASE}
MYSQL_ROOT_PASSWORD: ${DB_PASSWORD}
MYSQL_PASSWORD: ${DB_PASSWORD}
MYSQL_USER: ${DB_USERNAME}
volumes:
- ./database/dbdata:/var/lib/mysql
networks:
- myapp-network
phpmyadmin:
image: phpmyadmin:latest
container_name: phpmyadmin
ports:
# 8080 is the host port and 80 is the docker port
- 8080:80
environment:
PMA_HOST: mysql
UPLOAD_LIMIT: 20M
MYSQL_USERNAME: ${DB_USERNAME}
MYSQL_ROOT_PASSWORD: ${DB_PASSWORD}
restart: unless-stopped
networks:
# define your network where all containers are connected to each other
- myapp-network
networks:
myapp-network:
driver: bridge