Letsencrypt

	Skill level: Advanced
	The instructions on this page may require deviations from standard procedures. A good understanding of linux and Koozali SME Server is recommended.

	Warning:
	This procedure change the default certificates and could significantly compromise your server's security. Thorough understanding of linux system management is required. Proceed at your own risk

Introduction

Let’s Encrypt is a new Certificate Authority: It’s free, automated, and open. It's main purpose is to allow people to encrypt the internet traffic by a very simple system.

The certs delivered must be renewed every 3 months.

Installation

For the installation of Letsencrypt, the initial generation of the certificates and periodically re-new the authority certificates, at minimum Python version 2.7 is required. By default SME Server comes with a lower version, but below instruction will enable you to install version 2.7 in a 'supported' way, next to the default SME Server Python version. The newly installed Python version 2.7 will then only be used (after initial installation) for the renewal of the certificates (periodically and mandatory every 3 months).

Follow the instructions at Software_Collections and the python related wiki page specifically. One needs to add the scl-repository for Python 2.7 that can be found here

Then:

yum install python27 --enablerepo=scl-python27
yum install git

	Note:
	We need to see if installing GIT is really required, for the GIT version is also available as a ZIP file. The less we install, the better.

To use Let's Encrypt run:

scl enable python27 bash
mkdir /src
cd /src
git clone https://github.com/letsencrypt/letsencrypt.git
cd letsencrypt
service httpd-e-smith stop
./letsencrypt-auto certonly --standalone --email me@mydomain.co.uk -d test.firstdomain.co.uk -d seconddomain.co.uk -d www.seconddomain.co.uk

Replacing email and domains as required. Then configure SME with the certificates generated:

config setprop modSSL crt /etc/letsencrypt/live/test.firstdomain.co.uk/fullchain.pem
config setprop modSSL key /etc/letsencrypt/live/test.firstdomain.co.uk/privkey.pem
config setprop modSSL CertificateChainFile /etc/letsencrypt/live/test.firstdomain.co.uk/fullchain.pem
signal-event post-upgrade; signal-event reboot

	Note:
	We need to see if setting the above db variables disturbs other SME Server default functionality and contribs that work with certificates such as VPN solutions.

Renew of the certs

A simple script to renew cert :

#!/bin/bash
source /opt/rh/python27/enable
export X_SCLS="`scl enable python27 'echo $X_SCLS'`"
service httpd-e-smith stop
cd /src/letsencrypt
./letsencrypt-auto certonly --standalone --email me@mydomain.co.uk -d test.firstdomain.co.uk -d seconddomain.co.uk -d www.seconddomain.co.uk --renew-by-default
service httpd-e-smith start

You may want to set this up as a cron job to run every two months, to make sure your certificate doesn't expire. Please see Crontab_Manager contrib for an easy way to achieve this.

Backup

Your certificate, private key, and other important information are stored in /etc/letsencrypt, which is not included in the standard SME Server backup routines. Make sure to add this directory to your backups.

Source from info

Source: http://forums.contribs.org/index.php/topic,51961.msg266680.html#msg266680