Understanding Dedicated Hosting Uptime, and What is Uptime?
Posted on February 10th, 2009
Understanding Dedicated Hosting Uptime, and What is Uptime?
When it comes to dedicated hosting, VPS or good old shared hosting, uptime is the amount of time, in percentages, that the service is available. Obviously the higher the uptime the better, but most businesses with an online focus should look for 99.9% uptime or greater – especially for dedicated server hosting services. Uptime is also one of the main factors to consider when looking around. But to understand what exactly it means, think of it this way:
In January, there are 31 days with 24 hours in each. That’s 744 hours or 44,640 minutes. If your dedicated hosting provider goes offline for 20 minutes in January then their uptime would be 99.955%. ([44,640mins-20mins]/44,640mins*100percent)
As a quick reference, here’s a list of uptime percentages that you can use as a cheat sheet for determining your uptime. The numbers are based on a 31 day month:
* 99.999%: 27 seconds
* 99.99%: 4 minutes, 28 seconds
* 99.9%: 44 minutes, 38 seconds
* 99.5%: 3 hours, 43 minutes
* 99.0%: 7 hours, 26 minutes
As you’ve probably noticed, the last 0.1% makes a fairly significant difference. For dedicated hosting providers, it also means huge differences in infrastructure investments. As a result, be prepared to pay a premium the higher up the Uptime scale you need to go.