Andrew Hillier, co-founder and CTO, CiRBA (, says:

Momentum is key to many virtualization initiatives, and anything that can “stall” an initiative should be avoided. Failure to plan for adequate power and cooling can cause outages and/or force organizations to under-populate racks, causing projects to fall short on their goals to reduce floor space.

We see an increasing requirement for physical-to-rack, or “P2R” analysis. This is the process of modeling the utilization of physical servers based on the VMs they are hosting, and using these models to analyze servers into available rack capacity by using power consumption, U-factor and BTUs as constraints. This not only helps ensure fully loaded virtual hosts don’t overstress data center real estate, but allows alignment between the physical and logical aspects of the data center. For example, by modeling more advanced constraints on rack placement, such as application connectivity, security zones, resiliency requirements and other key considerations, the physical design of the infrastructure can fine tuned to match the needs of the applications it supports.

Another factor can impact the physical design of the data center is workload mobility, and in particular the ability to “motion” virtual machines between physical systems. Because this allows workloads to move between racks, rooms, and even data centers, it can have a revolutionary impact on application availability and disaster recovery. But the benefits this provides is closely tied to the physical design of the infrastructure, as you need to have the right capacity in the right physical location at the right time. For example, for virtual environments that span cabinets, cabinet failure analysis allows organizations to determine if a virtual environment will be able to re-balance itself across the servers in the remaining cabinets. If this analysis detects vulnerabilities in the physical design, it may be necessary to adjust rack locations, PDU associations and even the entire design of the data center in order to provide the necessary resiliency.