Taken from https://community.letsencrypt.org/t/complete-guide-to-install-ssl-certificate-on-your-os-x-server-hosted-website/15005?source_topic_id=33254&source_topic_id=40061
If like me you are, among other many tasks, a system administrator of a website hosted on OS X server, chances are your are not fully comfortable with what to do precisely in order to get your website running with a valid SSL certificate. After some struggle, I would like to share my experience on the installation of let’s encrypt certificate.
The target audience of this article is people with a minimum IT skills (I assume you know how to open the terminal and some basic knowledge of shell commands), already having a configured and running website hosted on OS X and managed with the Server App. Also this article assumes you will generate the certificate on the machine hosting the server itself.
Note: The following procedure was successfully installed on two similar server, both are Mac mini running on OS X Mavericks (10