This graphic depicts an example of grid hosts and the physical topography. Rack 1 contains hosts 3, 4, and 5. Hosts 3 and 4 are attached to power source 1. Host 5 uses power source 2. Hosts 3, 4, and 5 use air conditioner 1. Rack 2 contains hosts 6, 7, and 8. Hosts 6 and 7 use power source 3. Hosts 6, 7 and 8 use air conditioner 2.