Do you fall into the the 99.9 percentile for uptime? Why do most hosting companies offer this as a sign of uptime? How do you personally come up with this percentage?

I tell them what ever it is if it is one day or 90 days You can do the math part of it and figure out what the % is but if you really think about it. Uptime is kind of like I am better than you but in all reality it isn't

If you are concerned about this kind of thing then get a 3rd party to monitor you.

Yep and MRTG Graphs to show them as well when the busy times are on the server etc...

That's only of any use to anyone if you only have one or two servers and is usually misunderstood by clients anyway.

99.7% always. heck my computer is up 96% this month what does that tell you?

That you need to get some fresh air sometime soon

lol. We only just started getting a 3rd party monitor. We didn't feel the need before

What do you use?

www.siteuptime.com I think... It's free

I use easymonitor.com
Its free and it checks your site evey 15 minutes.

I tell customers 99.9% uptime, but it really has been 100% uptime ever sense the servers have been up. Just incase if something happens some day, this 99.9% uptime will give us a minute to fix the problem.

And how can you maintain that guarantee?

Well our servers are stored in a raised floor facility with (21) 26-ton Data Air AC units, Very Early Smoke Detection Apparatus (VESDA), Pre-action dry pipe sprinkler system. Security badge entry/exit on all doors to facility, (6) 500KVA Powerware UPS units, 1-megawatt generator (2000-gallon tank), 1.5-megawatt generator (2200-gallon tank).

Having that said it is almost impossible for our servers to go down. But I still say 99.9% because everything is possible.

So what? If the hardware is low quality, the servers overloaded or the sysadmins incompetent none of that will make any difference.