docker compose phpmyadmin php_network_getaddresses: getaddrinfo failed: Temporary failure in name resolution - docker-compose

Question

I am trying to set up a docker-pod with laravel, mariadb, nginx, redis and phpmyadmin. The laravel webspace works finde but if i switch to port 10081 like configured in the docker-compose.yml i am not able to login with the root account.
it sais " mysqli::real_connect(): php_network_getaddresses: getaddrinfo failed: Temporary failure in name resolution"
i already tried to configure a "my-network" which links all of the container, but if i understand docker right there is already a "defaul" network which does this. It didnt change the error message anyway.
here is my full docker-compose file
version: "3.8"
services:
redis:
image: redis:6.0-alpine
expose:
- "6380"
db:
image: mariadb:10.4
ports:
- "3307:3306"
environment:
MYSQL_USERNAME: root
MYSQL_ROOT_PASSWORD: secret
MYSQL_DATABASE: laravel
volumes:
- db-data:/var/lib/mysql
nginx:
image: nginx:1.19-alpine
build:
context: .
dockerfile: ./docker/nginx.Dockerfile
restart: always
depends_on:
- php
ports:
- "10080:80"
networks:
- default
environment:
VIRTUAL_HOST: cockpit.example.de
volumes:
- ./docker/nginx.conf:/etc/nginx/nginx.conf:ro
- ./public:/app/public:ro
php:
build:
target: dev
context: .
dockerfile: ./docker/php.Dockerfile
working_dir: /app
env_file: .env
restart: always
expose:
- "9000"
depends_on:
- composer
- redis
- db
volumes:
- ./:/app
- ./docker/www.conf:/usr/local/etc/php-fpm.d/www.conf:ro
links:
- db:mysql
phpmyadmin:
image: phpmyadmin/phpmyadmin:latest
ports:
- 10081:80
restart: always
environment:
PMA_HOST : db
MYSQL_USERNAME: root
MYSQL_ROOT_PASSWORD: secret
depends_on:
- db
#user: "109:115"
links:
- db:mysql
node:
image: node:12-alpine
working_dir: /app
volumes:
- ./:/app
command: sh -c "npm install && npm run watch"
composer:
image: composer:1.10
working_dir: /app
#environment:
#SSH_AUTH_SOCK: /ssh-auth.sock
volumes:
- ./:/app
#- "$SSH_AUTH_SOCK:/ssh-auth.sock"
- /etc/passwd:/etc/passwd:ro
- /etc/group:/etc/group:ro
command: composer install --ignore-platform-reqs --no-scripts
volumes:
db-data:

Answer 1

Make sure you have defined all attributes correctly for phpmyadmin container, in the current case there was the absence of -network definition
phpmyadmin:
image: phpmyadmin/phpmyadmin:latest
container_name: phpmyadmin
restart: always
ports:
# 8080 is the host port and 80 is the docker port
- 8080:80
environment:
- PMA_ARBITRARY:1
- PMA_HOST:mysql
- MYSQL_USERNAME:root
- MYSQL_ROOT_PASSWORD:secret
depends_on:
- mysql
networks:
# define your network where all containers are connected to each other
- laravel
volumes:
# define directory path where you shall store your persistent data and config
# files of phpmyadmin
- ./docker/phpmyadmin

Answer 2

Maybe your container cannot start because its volume contains incompatible data. It can happen if you downgrade the version of mysql or mariadb image.
You can resolve the problem if you remove the volume and import the database again. Maybe you have to create a backup first.