“Nines” can be turned into time
, for the purposes of discussions:
Uptime Monthly Downtime Annual Downtime
Five Nines 99.999% 0:00:26 0:05:11
Four Nines 99.99% 0:04:19 0:51:50
Three Nines 99.9% 0:43.12 8:38:24
Two Nines 99% 7:12:00 86:24:00
This assumes a thirty-day month, at twenty-four hours a day (720 Hours/Month). The annual number is simply twelve times the monthly (there may be some approximation). These figures should provide an idea what a given “nine” provides, though should be validated before writing it into a service level agreement.