2FANGINX is an auth module for 2FA (2 factors authentication) on NGINX (using "standard" Lua module from NGINX). It allows you to protect using 2FA a whole subdomain, without interfering with other security mesures below the domain hierarchy.
Features
Securely hashed (HMAC-SHA1) cookie (distributed only on HTTPS)
Always use the most accessible software, and do not need to recompile a full NGINX isntance. So using the default NGINX Ubuntu/Debian package and the default Lua module addon also available as a package (libnginx-mod-http-lua).