Intelligent CIO Middle East Issue 24 | Page 37

FEATURE: DATA CENTRE COMMISSIONING “When considering availability all the key systems such as critical IT, power distribution and cooling will need to be correctly balanced against the business needs.” to evaluate the amount of space required for a data centre build. The initial design factor is to understand the number of cabinets, size of planned cabinets and their projected power density. Knowing this will allow you to then calculate the additional space requirements or restrictions for factors such as: • Deployment of cabinets (simple hot/ cold aisle, hot/cold aisle containment systems or zone deployment) • Architectural restrictions within the whitespace such as entrance/exit clearances, structural pillars or raised floor ramps. • Power (PDUs and/or RPPs) and air conditioning units. The number may increase subject to the level of availability required. • Potential reserved whitespace for future IT builds. • Any sub-divisions or separate rooms within the whitespace area. Modern data centre builds now endeavour to move the power and cooling units outside the whitespace area into service corridors or adjacent dedicated rooms to maximise the space for cabinet deployment. What is the best way of determining the number of Rack Location Units (RLUs) that will be required? www.intelligentcio.com The availability of whitespace needs to be accurately measured to understand the usable space that is available for rack population deployment. The next step is to understand the dimensions of the range of IT equipment to be housed in the designated racks (standard 19-inch rack-mountable equipment). Then the cabinet dimensions (height x width x depth) and the load factor need to be calculated. However, its not quite that simple as the power and cooling availability may restrict the actual RLU size that can be deployed. What sort of wattage per RLU is considered to be a high-density deployment? There are many differing views on what cabinet wattage is now considered to be high-density but that is primarily due to different building architecture and IT operating environments. That said, today’s general data centre industry view is that seems to consider 10–12kW cabinets as high-density. Do high density deployments need additional amounts of supporting infrastructure? The answer is simply ‘yes’ there will be the requirement for additional supporting infrastructures to support a high-density design. Factors such as: • Adequate power distribution availability (possibly at higher voltage supplies) and supporting standby systems (UPS and Generators). • Appropriate cooling systems will be required to remove the increased level of heat dissipation created from the IT cabinets. • Implementation of Hot Aisle Containment (HAC) systems to support the heat removal. • Floor loading to support the additional weight demand (raised access floors unlikely to be utilised for high-density environments). • Appropriately design power and data containment systems. How can the ratio of support space to IT space be determined? The support space (i.e. electrical and mechanical) will be very much orientated by the size of the IT whitespace and the projected density (present to future) of the IT cabinets. Plus, additional areas such as offices, workshops and storage areas required to support the operational needs of the data centre. There are numerous space calculators available to provide a good baseline before adding the precise build needs. How important is it to consider Availability Requirements? There are many factors (internal and external) that are likely to influence the considerations when deciding on the level of availability for a data centre. The first factor is to really understand what availability means. It is the “There are numerous space calculators available to provide a good baseline before adding the precise build needs.” period of time or proportion of that period for which critical IT systems are available and operational. In simple terms availability defines the difference between uptime and downtime. So, when considering availability all the key systems such as critical IT, power distribution and cooling will need to be correctly balanced against the business needs. If downtime is an unacceptable risk to the business, the availability levels are likely to be higher to ensure constant uptime. What does a CIO commissioning a data centre solution need to consider regarding budget requirements? INTELLIGENTCIO 37