Copied over the relevant parts from the README

Configuration.md

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+# Configuration
+
+You can configure the app using environment variables.
+These are defined in `netbox.env`.
+Read [Environment Variables in Compose][compose-env] to understand about the various possibilities to overwrite these variables.
+(The easiest solution being simply adjusting that file.)
+
+To find all possible variables, have a look at the [configuration.py][docker-config] and [docker-entrypoint.sh][entrypoint] files.
+Generally, the environment variables are called the same as their respective Netbox configuration variables.
+Variables which are arrays are usually composed by putting all the values into the same environment variables with the values separated by a whitespace ("` `").
+For example defining `ALLOWED_HOSTS=localhost ::1 127.0.0.1` would allows access to Netbox through `http://localhost:8080`, `http://[::1]:8080` and `http://127.0.0.1:8080`.
+
+[compose-env]: https://docs.docker.com/compose/environment-variables/
+
+## Configure for Production
+
+The default settings are optimized for (local) development environments.
+You should therefore adjust the configuration for production setups, at least the following variables:
+
+* `ALLOWED_HOSTS`: Add all URLs that lead to your Netbox instance, space separated. E.g. `ALLOWED_HOSTS=netbox.mycorp.com server042.mycorp.com 2a02:123::42 10.0.0.42 localhost ::1 127.0.0.1` (It's good advice to always allow localhost connections for easy debugging, i.e. `localhost ::1 127.0.0.1`.)
+* `DB_*`: Use your own persistent database. Don't use the default passwords!
+* `EMAIL_*`: Use your own mailserver.
+* `MAX_PAGE_SIZE`: Use the recommended default of 1000.
+* `SUPERUSER_*`: Only define those variables during the initial setup, and drop them once the DB is set up. Don't use the default passwords!
+* `REDIS_*`: Use your own persistent redis. Don't use the default passwords!