Problem bringing Yourls service up

[diggidre]

Hey guys,
I have a problem with starting yourls container.
I followed the docker hub description but when I go to my yourls sub I get an Error 504.
The yourls container log says
MySQL Connection Error: (2002) php_network_getaddresses: getaddrinfo failed: Name or service not known
I use docker on raspbian that runs on a pi4b with traefik v1.7.30 and nextcloud 21 already up and running.
Here is my yourls docker-compose.yml

version: '3.1'

services:

  yourls:
    image: yourls
    restart: always
    ports:
      - 8008:80 # 8080 is already in use
    environment:
      YOURLS_DB_PASS: xxx
      YOURLS_SITE: https://sub.mydomain.xxx
      YOURLS_USER: root
      YOURLS_PASS: xxx
      YOURLS_DB_HOST: name of the mariadb service > same as I use for nextcloud
      YOURLS_DB_NAME: yourls
      
    labels:
      - "traefik.enable=true"
      - "traefik.backend=sub.mydomain"
      - "traefik.frontend.rule=Host:sub.mydomain.xxx"
      - "traefik.docker.network=traefik"
      - "traefik.port=80"
            
    networks:
      - traefik
      
networks:
  traefik:
    external:
      name: traefik
  default:
    driver: bridge

sry could not pastebin the code because pastebin says code is potentially offensiv ...

[LeoColomb]

There are two issues in your message:

1. Error 504
   Which page are you trying to access?
   What is the log of Treafik?
   Could you reach it without Treafik? (using ip address or internal name)
2. MySQL Connection Error: (2002) php_network_getaddresses: getaddrinfo failed
   Is this only visible at the startup or appear regularly? If only startup, everything is fine, if not, some issue while resolving mysql server name.