Manual mod_cloudflare Install and Update
Introduction
This quick guide is based of the official documentation: https://www.cloudflare.com/resources-downloads
These steps worked for me on Ubuntu 15.04 and Ubuntu 16.04.
Install and/or Update
The following batch of lines performs both the initial install and updates existing installs:
apt-get install libtool apache2-dev --yes
cd /tmp
wget https://www.cloudflare.com/static/misc/mod_cloudflare/mod_cloudflare.c
apxs2 -a -i -c mod_cloudflare.c
service apache2 restart
rm mod_cloudflare.*