Styjun

Impossible to connect to frontends with HTTPS with a specific domain: Error 502 or Error 504 (db or webmail)
I am using 3 YAML files:
1 for traefik
1 for subdomain 1, 1 for subdomain 2

Traefik and domain 1 configuration are OK, the problem is on subdomain2. The network configuration in docker-compose is nearly the same between subdomain1 et subdomain2. Restarting and recreating the container doesn't change anything.

traefik.yaml
version: '3'

networks:
 internal:
 internal: true
 external: false
 prometheus:
 external:
 name: dockerprometheus_back-tier

services:
 reverse-proxy:
 image: traefik #The official Traefik docker image
 container_name: traefik
 command: --api --docker --docker.domain=domain.local
 ports:
 - "80:80" #The HTTP port
 - "443:443" #The HTTPS port
 labels:
 - traefik.enable=true
 - traefik.frontend.rule=Host:mail.prekre.com
 - traefik.port=8080
 - traefik.docker.network=prometheus
 expose:
 - "8090"
 env_file:
 - ./prekre.env
 volumes:
 - /var/run/docker.sock:/var/run/docker.sock #So that Traefik can listen to the Docker events
 - ./traefik2.toml:/traefik.toml
 - ./acme.json:/acme.json
 restart: always

 command: --api --docker --docker.domain=domain.local #Enables the web UI and tells Træfik to listen to docker
# command: --web --web.metrics.prometheus --web.metrics.prometheus.buckets="0.1,0.3,1.2,5.0" --docker --docker.domain=domain.local --logLevel=DEBUG
 networks:
 - prometheus
 ports:
 - "80:80" #The HTTP port
 - "443:443" #The HTTPS port
 labels:
 - traefik.enable=true
 - traefik.frontend.rule=Host:mail.prekre.com
 - traefik.port=8080
 - traefik.docker.network=prometheus
 expose:
 - "8090"
 env_file:
 - ./prekre.env
 volumes:
 - /var/run/docker.sock:/var/run/docker.sock #So that Traefik can listen to the Docker events
 - ./traefik2.toml:/traefik.toml
 - ./acme.json:/acme.json
 restart: always

sub1.yaml:

version: '3'

networks:
 onlykoreainternal:
 driver: bridge
 external: false
 internal: true
 prometheus:
 external:
 name: dockerprometheus_back-tier


sub2.yaml
version: '3'

networks:
 mail_network:
 driver: bridge
 external: false
 internal: true
 prometheus:
 external:
 name: dockerprometheus_back-tier

services:
 mailserver:
 image: hardware/mailserver:$MAILSERVER_DOCKER_TAG
 container_name: mailserver
 restart: $RESTART_MODE
 domainname: $MAILSERVER_DOMAIN # Mail server A/MX/FQDN & reverse PTR = mail.domain.tld.
 hostname: $MAILSERVER_HOSTNAME
 labels:
 - traefik.enable=true
 - traefik.frontend.rule=Host:spam.$MAILSERVER_DOMAIN
 - traefik.port=80
 - traefik.docker.network=prometheus


services:
 mailserver:
 image: hardware/mailserver:$MAILSERVER_DOCKER_TAG
 container_name: mailserver
 restart: $RESTART_MODE
 domainname: $MAILSERVER_DOMAIN # Mail server A/MX/FQDN & reverse PTR = mail.domain.tld.
 hostname: $MAILSERVER_HOSTNAME
 labels:
 - traefik.enable=true
 - traefik.frontend.rule=Host:spam.$MAILSERVER_DOMAIN
 - traefik.port=80
 - traefik.docker.network=prometheus
 # extra_hosts: - Required for external database (on other server or for local databases on host without docker)
 # - "mailmariadb:xx.xx.xx.xx" - Replace with IP address of MariaDB server
 # - "redis:xx.xx.xx.xx" - Replace with IP address of Redis server
 ports:
 - "25:25" # SMTP - Required
 # - "110:110" # POP3 STARTTLS - Optional - For webmails/desktop clients
 - "143:143" # IMAP STARTTLS - Optional - For webmails/desktop clients
 # - "465:465" # SMTPS SSL/TLS - Optional - Enabled for compatibility reason, otherwise disabled
 - "587:587" # Submission STARTTLS - Optional - For webmails/desktop clients
 - "993:993" # IMAPS SSL/TLS - Optional - For webmails/desktop clients
 # - "995:995" # POP3S SSL/TLS - Optional - For webmails/desktop clients
 - "4190:4190" # SIEVE STARTTLS - Optional - Recommended for mail filtering
 env_file:
 - mail.env
 environment:
 - DBPASS=$DATABASE_USER_PASSWORD # MariaDB database password (required)
 - RSPAMD_PASSWORD=$RSPAMD_PASSWORD # Rspamd WebUI password (required)
@

Same declaration in traefik.tom for sub1 and sub2 for DNS.
Have you any ideas about the bug?

Change the network inside the container (1 private and 1 host for each front-end, only 1 private/internal for databases).
Check logs (nothing interresting)