Dashboard only working with insecure=true

Hello my friends,
first of all, I've read and tested quite a bit on this subject. But after 20 hours without a working solution i thought its better to freez my current config an ask for help :slight_smile:

Issue:
WIth insecure=true i can easlie access the dashboard on sub.domain.tld:8088/dashboard/
but after removing insecure=true it doesnt work any more. You only get a black page with "404 page not found" an the request shows up in the access.log file.
Tested following Requests: http://proxy.sub.domain.tld:8088, https://proxy.sub.domain.tld:8088, http://ip:8088, https://ip:8088 (replace IP with local and external ipv4)

Version
2.8.0

Docker run

docker run -d    \
-v /var/run/docker.sock:/var/run/docker.sock    \
-v /mnt/nfs-share/traefik/config/traefik.toml:/traefik.toml    \
-v /mnt/nfs-share/traefik/config/traefik_dynamic.toml:/traefik_dynamic.toml  \  
-v /mnt/nfs-share/traefik/config/acme.json:/acme.json    \
-v /mnt/nfs-share/traefik/config/access.log:/access.log \
-v /mnt/nfs-share/traefik/config/log-file.log:/log-file.log \
-p 80:80    \
-p 443:443  \
-p 8088:8088   \
--label traefik.enable=true \
--network web    \
--name traefik_latest  \  
traefik:latest

traefik.toml

[entryPoints]
  [entryPoints.web]
    address = ":80"
    [entryPoints.web.http.redirections.entryPoint]
      to = "websecure"
      scheme = "https"

  [entryPoints.websecure]
    address = ":443"

  [entryPoints.traefik]
    address = ":8088"

[api]
  dashboard = true
  #insecure = true

[certificatesResolvers.lets-encrypt.acme]
  email = "info@my.tld"
  storage = "acme.json"
   [certificatesResolvers.lets-encrypt.acme.httpChallenge]
      # used during the challenge
      entryPoint = "web"

[providers.docker]
  watch = true
  network = "web"
  exposedbydefault = false
[providers.file]
  filename = "traefik_dynamic.toml"

[log]
  filePath = "log-file.log"
  format = "json"
  level = "DEBUG"
[accessLog]
  filePath = "access.log"
  format = "json"

traefik_dynamic.toml

[http.routers.api]
  rule = "Host(`proxy.sub.domain.tld`) && (PathPrefix(`/api`) || PathPrefix(`/dashboard`))" 
  entrypoints = ["websecure"]
  middlewares = ["simpleAuth"]
  service = "api@internal"
  [http.routers.api.tls]
    certResolver = "lets-encrypt"

[http.middlewares.simpleAuth.basicAuth]
  users = [
    "admin:$XXXXXXXXXXXXXXXXXXXXX",
  ]


[tls.options]

  [tls.options.default]
    minVersion = "VersionTLS12"

  [tls.options.mintls13]
    minVersion = "VersionTLS13"

This is my current version of my config. As already said i tested a bunch of diffrent configs and stuff. The "log-file.log" only shows debug messages, no warnings or any errors.

If someone has any ideas i would love to hear them :slight_smile: