The Cost of High Availability


99.99% availability, also known as four nines availability, requires a system to only have 52.60 minutes of downtime per year, which corresponds to 4.38 minutes of downtime per month. It is the most achievable and optimal availability model for most systems.When cloud computing entered the market, 99.99% availability cost a lot of money. Obtaining 99.9% availability could cost thousands per month, with 99.99% availability usually costing tens of thousands per month. The magnitude of cost when it came to 99.999% availability was around a whopping 100k per month!Achieving 99.99% availability several years ago required the following items: