diff --git a/doc/rpm-build/nginx.conf b/doc/rpm-build/nginx.conf
index 55cc8622a3..2b4860ef3e 100644
--- a/doc/rpm-build/nginx.conf
+++ b/doc/rpm-build/nginx.conf
@@ -12,11 +12,19 @@ server {
 	# HTTP Strict-Transport-Security header (start with a short max-age!)
 	#add_header Strict-Transport-Security max-age=31536000;	# 31536000sec=1year
 
+	# A free of charge ssl certificate can be obtained from https://letsencrypt.org
+	# Instrunctions for Ubuntu 16.04 are eg. available at
+	# https://www.digitalocean.com/community/tutorials/how-to-secure-nginx-with-let-s-encrypt-on-ubuntu-16-04
+	# Just use /etc/egroupware/nginx.conf instead of /etc/nginx/sites-available/default
+
 	server_name _;
 	root /var/www/html;
 
 	index index.php index.nginx-debian.html index.html index.htm;
 
+	# include other EGroupware parts like Collabora
+	include app.d/egroupware*.conf;
+
 	# EGroupware installed in /usr/share/egroupware
 	location ^~ /egroupware {
 		alias  /usr/share/egroupware/;