...
http://githubengineering.com/rearchitecting-github-pages/
VMs
Hostnames and IPs
sca-nginx01 is deployed on > scalnx12-vmm with 12GB memory and 6 cores
sca-nginx02 is deployed on > scalnx13-vmm with 12GB memory and 6 cores
Both will share the sca-www hostname through the virtual IP address 134.79.129.86.
Management of the Virtual IP address will be handled with keepalived.