Can't connect Mac Client ("Network Error: Handshake Failed")

Tried on several different Macs via service URL. Local IP address works fine. iOS clients work fine as well (both with service URL and local IP address). None of my other self hosted services ever had SSL issues.

Setup:

  • Ubuntu Server
  • Docker
  • Traefik as reverse proxy
  • SSL certificate via LetsEncrypt in Traefik

Excerpt from my docker compose file:

    environment:
      SEAFILE_SERVER_HOSTNAME: seafile.${DOMAIN_PRIVATE}
      SEAFILE_SERVICE_URL: https://seafile.${DOMAIN_PRIVATE}
      SEAFILE_FILE_SERVER_ROOT: https://seafile.${DOMAIN_PRIVATE}/seafhttp
      # SEAFILE_SERVER_LETSENCRYPT: false
      # FORCE_HTTPS_IN_CONF: false
    labels:
      traefik.http.routers.seafile.rule: Host(`seafile.${DOMAIN_PRIVATE}`)
      traefik.http.routers.seafile.tls: true
      traefik.http.routers.seafile.tls.certresolver: lets-encrypt
      # traefik.http.routers.seafile.middlewares: chain-no-auth@file
      traefik.http.services.seafile.loadbalancer.server.port: 80

Could anyone maybe provide hints how to debug this? Am I doing something wrong?

I suspect this has something to do with Seafile not supporting TLS 1.3. Could anyone tell me how to remedy this? What do other people who are able to use the Mac client do differently than me?

Anyone suggestions to troubleshoot this would be appreciated!