Currently, the Nginx configuration is created on each VM in the VMSS as they boot up. This means that it's not possible for users to use a custom Nginx config file (e.g. to enable URL rewrite, or to change some PHP settings, or use a subfolder as webroot...).
I suggest we instead generate the Nginx config files in the controller, putting them in /azlamp, and replicate them across the VMSS. This way, customers could manually alter the config if necessary.