Data centers are at the heart of every cloud business. As we explained in a previous article, they are divided into different classifications. But some preconceived ideas can be misleading.
According to Xerfi, 156 data centers are based in France (March 2018 study). Île-de-France is home to 56 hosting and management companies, including the largest. They are classified according to different levels and certifications. These are issued by the Uptime Institute. It created the TIER classification system to consistently assess different datacenter facilities in terms of potential performance and/or uptime.
But what guarantees do TIER certifications really provide? These different levels of classification mean that a particular datacenter can be chosen according to the specific needs or requirements of a company or organization.
The performance and capacity of a datacenter infrastructure must therefore correspond to the specificities of a business application or imperative. A university has less stringent performance requirements than a clinic.
Another example: a small law firm may be satisfied with a TIER I, while a large-scale e-commerce site will need to rely on a TIER III or IV.
Finally, a SaaS application publisher that replicates its data elsewhere may not need a Level III or IV installation.
This is the main rule: choose the "right" datacenter to avoid over-investing or, on the contrary, taking too many risks. And, of course, don't believe certain myths and prejudices.
#1 - TIER IV is the best certification for data centers
No. It doesn't make sense. TIER IV is not necessarily the best answer for every organization, depending on the priority criteria chosen by management.
TIER I and II solutions generally focus on cost and time-to-market rather than on performance requirements (uptime).
But if a company wants to benefit from long-term availability and viability, it will opt for levels III and IV.
In a Level III installation, each component can be taken out of service according to a schedule (maintenance, for example), without affecting the critical environment or IT processes.
Level IV solutions are even more robust. Every component and every connection can withstand a failure, error or unforeseen event without affecting the critical environment or IT processes.
#2 - TIER certifications specify an estimated downtime per year
No. The Uptime Institute removed references to "expected downtime per year" from TIER certification in 2009. In any case, they were never part of the certification definitions. There are, however, statistical tools for predicting failure frequency and recovery time.
However, care must be taken when using these tools. Human activity is often not taken into account.
#3 - All cooling units in a TIER IV installation must operate
No. Cooling is indeed an important criterion for data center managers. But TIER IV certification only requires that facilities provide stable cooling to the environment for as long as it takes for mechanical systems to restart after a power failure.
These TIERs must also maintain a stable thermal environment throughout mechanical restart and for 15 minutes, in accordance with the thermal guidelines of the American Society of Heating, Refrigerating and Air-conditioning Engineers (ASHRAE).
#4 - Datacenter location affects level
No. Although a critical factor for infrastructure, location has no impact on certification. Nevertheless, data center managers need to put in place various measures to mitigate site-specific risks. A data center located in a high-risk seismic zone needs to integrate specific equipment.
Infrastructure installed in high-risk tornado zones must be designed to protect electrical equipment from gusts. Heat discharge to the outside must also be limited. A layer of warm, moist air above a cold air mass can be the source of a tornado.
#5 - Certifications only apply to recent installations
No. Uptime Institute has certified many existing buildings. But the process can be more difficult when auditing facilities with resource-intensive activities.
In the end, the choice of datacenter depends above all on the criticality of the business and how it plans to use the cloud in its long-term strategy.
