What you should consider when right-sizing a data center
How does an organization decide the appropriate size and density for its data centers? Consider factors such as rack layout and available power first.
Your data center's size depends on the size of your organization and its resources. To determine the appropriate size and density of your data center, consider the technology available to you and your budget for facilities.
As server consolidation technologies such as virtualization and more advanced processors continue to grow, many organizations have shifted away from measuring their data centers' size by physical space and toward measuring size by density. This density determines how much power your data center consumes. You can determine your data center's size and density by knowing its compute space and peak kilowatt load. AFCOM ranks data center density in four categories: low, medium, high and extreme.
Even though the same square footage can now hold increasing amounts of servers and storage arrays, you must still consider your data center's physical size. Square footage factors into discussions around layout and can contribute significantly to the issue of density. Use it to estimate capacity and utilization in a given data center room.
What's the right data center size for you?
Different types of organizations and different industries require different data center sizes and densities. A variety of factors can affect your data center's sizing needs, from server configurations to network architectures, as well as the age of your hardware. For example, if you still use quite a bit of legacy technology, then consider a smaller data center with more traditional network and server architecture.
When scaling up your data center, you might look into increasing your density by consolidating your servers and introducing newer processing technologies. This enables you to maintain the same physical footprint with additional compute capacity.
Why does data center size matter?
Large data centers are no more efficient than small and vice versa. Regardless of your data center's size, your priority in its design should be efficiency.
Larger data centers do have a few advantages over smaller ones, including room to scale and certain tools. In larger data centers, you can implement data center infrastructure management (DCIM) tools to monitor and manage your facilities. DCIM means including additional devices and software in your data center, which means an increased workload for staff. This makes DCIM more suitable for larger-sized data centers that have the resources to implement it and where the investment can pay off.
For smaller data centers, introducing virtualization can increase efficiency. Virtualization lowers space, power and cooling requirements, and simplifies workload migration, data protection and other server tasks.
Sizing a UPS unit
Your data center's size determines its power usage. You can figure out the size of your uninterruptable power supply (UPS) by measuring a handful of metrics. AC power sources are more efficient than DC for power companies to deliver, but AC power exhibits reactance, which reduces the amount of usable power available.
To calculate your data center's required power, use the formula watts = volts x amps x power factor, where power factor is the ratio of available, usable power to total supplied power. Once you determine your power requirements, plan to run your UPS at roughly 80% of your power capacity. For example, if you have a planned load of 80 kW, you should use a 112.5 kW system with a power factor of 0.9. This gives you some wiggle room in the event that you occasionally require more power and also gives you the capacity to install a duplicate power system.
Set up server racks correctly
Proper server rack setup depends on your data center's size. To avoid server rack issues, consider the size of your racks as well as the size of your space. Most racks can accommodate servers up to 19 inches wide, but you must also account for the height and depth of server racks when planning your use of space. Some server racks leave room for power and network cabling, but others do not.
Rack dimensions can vary from vendor to vendor, so ensure that you know the exact width, height and depth of your server racks, and that you understand how to fit these into your floor plan. Even slightly oversized racks can disrupt airflow and containment, especially in a data center layout with a tight and specific configuration.
