Update README.md

README.md

@@ -58,6 +58,35 @@ On OSX, these are available via Homebrew.
 * [Basic Introduction to EOTK](https://www.youtube.com/watch?v=ti_VkVmE3J4)
 * [Rough Edges: SSL Certificates & Strange Behaviour](https://www.youtube.com/watch?v=UieLTllLPlQ) 
 
+# Troubleshooting
+
+Firstly, the logs for any given project will reside in `projects.d/<PROJECTNAME>.d/logs.d/`
+
+## Nginx: Bad Gateway
+
+Generally this means that Nginx cannot connect to the remote website, which generally happens because:
+
+* the site name in the config file, is wrong
+* the nginx daemon tries to do a DNS resolution, which fails
+
+Check the Nginx logfiles in the directory cited above, for confirmation.
+
+If DNS resolution is failing, *PROBABLY* the cause is not running a DNS server locally; therefore in your config file you should add a line:
+
+```
+set nginx_resolver 8.8.8.8
+```
+
+...and then do:
+
+```
+eotk stop -a
+eotk config filename.conf
+eotk start -a
+```
+
+I will look into hardcoding the Google DNS server as a default.
+
 # User Manual
 
 Intuitively obvious to the most casual observer: