This is just a sample nginx config making using of SSL and reverse proxy to an app server for reference.

The idea is to have one of app-specific config file, with a singular server block, per website/app which is being controlled by nginx. These settings are different from the "global" settings found in the main nginx.conf file and should be tailored to the needs of your website/app.

I am loading a Node.js app behind a reverse proxy using nginx's upstream syntax to point to the Node.js server. This makes it much easier to let nginx handle terminating TLS connections and then (behind nginx) using a plain http connection to the Node.js server (this connection is internal, so it should be secured by the host's network security). The Node.js server will have no outside public-facing ports opened so that the only way of connecting to it will be through nginx.

The default nginx version on Ubuntu 14 is a bit old (e.g., 1.4), but it's easy to upgrade to the latest version using nginx's own stable repo:

sudo add-apt-repository ppa:nginx/stable
sudo apt-get update
sudo apt-get upgrade
sudo apt-get upgrade nginx
sudo service nginx restart

Mozilla has a great online SSL Config Generator that you can use to get some solid suggestions for your setup (not just nginx).