99.995% data center uptime, also known as "four and a half 9's" is 28 minutes of downtime per year or less. That's low downtime. But how do you achieve it?
Rated-4 data centers are expected to deliver this level of uptime via two of everything in the power, cooling and telecom infrastructures. This "two of everything" approach, also known as N+N data center redundancy or 2N data center redundancy, reduces the risk of downtime to 28 minutes per year or less.
But two of everything is expensive. And difficult to maintain. Most in-house enterprise data centers do not build to this high standard. CFOs tend avoid high data center capital costs and look towards cutting where they can. Which means an increase in downtime.
How do you achieve 99.995% uptime without building your own? Employ cloud computing data centers built with N+N redundancy. Use wholesale colocation facilities that build to the Rated-4 and TIA-942 data center standards.