From 4106cf647b5fb284b83d33d476b75a43bbcc07f3 Mon Sep 17 00:00:00 2001
From: Greg Berns <gregberns@users.noreply.github.com>
Date: Fri, 3 May 2019 01:28:05 -0700
Subject: [PATCH] Docs: Troubleshooting help for Docker Swarm labels

---
 docs/configuration/backends/docker.md | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/docs/configuration/backends/docker.md b/docs/configuration/backends/docker.md
index d43ea6a92..0735286cd 100644
--- a/docs/configuration/backends/docker.md
+++ b/docs/configuration/backends/docker.md
@@ -257,6 +257,20 @@ services:
         traefik.docker.network: traefik
 ```
 
+Required labels:
+
+- `traefik.frontend.rule`
+- `traefik.port` - Without this the debug logs will show this service is deliberately filtered out.
+- `traefik.docker.network` - Without this a 504 may occur.
+
+#### Troubleshooting
+
+If service doesn't show up in the dashboard, check the debug logs to see if the port is missing:
+`Filtering container without port, <SERVICE_NAME>: port label is missing, ...')`
+
+If `504 Gateway Timeout` occurs and there are networks used, ensure that `traefik.docker.network` is defined. 
+The complete name is required, meaning if the network is internal the name needs to be `<project_name>_<network_name>`.
+
 ### Using Docker Compose
 
 If you are intending to use only Docker Compose commands (e.g. `docker-compose up --scale whoami=2 -d`), labels should be under your service, otherwise they will be ignored.