Add more common causes for 502. Also ToC

general/swag.md

@@ -28,6 +28,10 @@ The goal of this guide is to give you ideas on what can be accomplished with the
   * [Nextcloud subdomain reverse proxy example](#nextcloud-subdomain-reverse-proxy-example)
   * [Plex subfolder reverse proxy example](#plex-subfolder-reverse-proxy-example)
   * [Using Heimdall as the home page at domain root](#using-heimdall-as-the-home-page-at-domain-root)
+* [Troubleshooting](#troubleshooting)
+  * [Common errors](#common-errors)
+    * [404](#404)
+    * [502](#502)
 * [Final Thoughts](#final-thoughts)
   * [How to Request Support](#how-to-request-support)
 
@@ -1175,6 +1179,13 @@ This error means that nginx can't talk to the application. There is a few common
 
     Also covered in the section for [Understanding the proxy conf structure](#understanding-the-proxy-conf-structure)
 
+* The container originally ran with host networking, or the default bridge.
+
+    In most cases the contents of `/config/nginx/resolver.conf;` should be `...resolver 127.0.0.11 valid=30s;`, if this is not the case, you can:
+
+    * Delete it, and restart the container to have it regenerate
+    * Manually set the content(we wont override it)
+
 # Final Thoughts
 
 This image can be used in many different scenarios as it is a full fledged web server with some bells and whistles added. The above examples should be enough to get you started. For more information, please refer to the official documentation on either [Github](https://github.com/linuxserver/docker-swag/blob/master/README.md) or [Docker Hub](https://hub.docker.com/r/linuxserver/swag). If you have questions or issues, or want to discuss and share ideas, feel free to visit our discord: https://discord.gg/YWrKVTn