The following tutorial considers that one is already a CloudFlare Partner, have memcached installed, and if running a firewall make sure that TCP port 2408 is open for both in and out of the firewall - this is the port Railgun listens on.
1. Logged in as root in ssh run:
rpm -ivh http://pkg.cloudflare.com/cloudflare-release-latest.el7.rpm
rpm -ivh http://pkg.cloudflare.com/cloudflare-release-latest.el6.rpm
rpm -ivh http://pkg.cloudflare.com/cloudflare-release-latest.el5.rpm
2. Logged in as root in ssh run: yum install railgun-stable
Note: Installing the package will automatically add /etc/init.d/railgun to be started on boot
3. Configuration and activation - this part is just a bit tricky and on our systems one wants to ssh to /etc/railgun/and modify the railgun.conf file adding/modifying:
activation.token = YOUR_TOKEN_HERE
activation.railgun_host = YOUR_PUBLIC_IP_OR_HOSTNAME
The activation.token comes from CloudFlare when adding a new Railgun https://partners.cloudflare.com/railguns and of course you should already know the servers main IP address ~or~ servers hostname.
4. Starting Railgun in ssh: service railgun start
5. On the CloudFlare Railgun page now refresh the page and it should show the new Railgun is activated and all that is left for us to do is add IP's by clicking in the center of the IP box and adding IP's or IP using CIDR format.
Done - Railgun is now installed and ready to be used.
To check the version of Railgun running in ssh: rg-listener --version