Mini Tutorial:99.5% / 99.9% uptime guarantee explained.

webmaster3000

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99.5% / 99.9% uptime guarantee explained.


A site that is “down” is as good as not having a site at all – no visitors, no traffic, no revenue, nothing – zilch. Because of this, a very high uptime guarantee percentage should be your top, or at the very least, major criterion when choosing a host.


Not too long ago, the hosting industry was looking at 99%, then later 99.5%. These days, some people say you should never settle for anything less than 99.9% as 99.9% beginning to become the "industry standard"/the norm. As more and more hosts offering 99.9%, those offering less than that will surely lose out in the competition simply because uptime is so important to website owners.


But what does this percentage really mean ? It is actually a simple calculation :

the total number of minutes in a month x (100-uptime%)/100
= 30days x 24hours x 60min x (100-99.9)/100
= 43200 x (0.1)/100
= 43.2 minutes (max downtime).


So, if it is 99.9%, it means your website should not be down for more than a total of about 43.2 minutes in a month. Mind you, the total number of minutes in a month is about 43200 minutes or 720 hours. So, 0.1% of downtime is actually very minimal. Out of this much time, your host should only down your site for a max of 43.2 minutes – whether it is for maintenance work, reboot, troubleshooting (because some monkey shares the same server as you and ran some mass emailing program/malicious script that cause CPU usage to go red ? ), change of failed hardware etc.


This does not mean that your site will be down for 43 minutes every month. That figure is actually the longest or maximum down time. Some good hosts might actually give you 100% uptime for months in a row in reality – even though they state 99.9% for the guarantee that they provide. These are hosts that take care of their CPU / RAM / executable file security etc – overall server environment properly.


Logically, the more domains/websites you plan to host in a single account, the higher percentage you should look for.


Also, do know how committed a host is in honouring their guarantee. Do they just mention it in their marketing channels, eg websites etc. Or do they really specify it clearly in their “terms of service” (ToS) / "Service Level Agreement" (SLA) ? What kind of compensation they plan to honour if they exceed the agreed upon max downtime ? Not all host are willing to compensate for exceeding the max downtime. Honest and responsible hosts will refund the hosting fees you paid for a particular month upon you reporting to them that they had exceeded the max downtime - and this is stated clearly in their ToS.

Also, note that not all hosts guarantee 99.5%/99.9% uptime for both their network and server uptime. Choose hosts that guarantee both.

Hope this mini article helps. For 2 hosts that I know of that explicitly specify their guarantee of 99.9% uptime in their agreements (ToS/SLA), refer to <<MOD NOTE: Advertising is not allowed.>> Not many hosts explicitly specify their uptime guarantee in their agreements.
 
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even a small different between 99.9 and 99.99 make big differences in uptime.

like what you said 99.9 is 43 min downtime, and 99,99 is only 4 min downtime. 40 min downtimes different
 
For personal and medium type of sites, 99.9% uptime is a good deal. But for mission critical or business sites you should always look for 100% uptime guarantee.

You don’t know when your site will be down even if for few minutes. The 4 minutes could be the time when a user was about to fill his CC info for a big order.
 
I have never liked 99% uptime guarentee's. In the IT world there are so many things that can go wrong it's not funny, and to offer a 99% uptime is an insult to the customer if you ask me.

My goal is always to have 100% uptime and that's what I tell my customers. Will I guarantee it? It's impossible for anyone to guarentee that your server will stay up, in fact in six years of hosting I have yet to be on a host that's not had some downtime. Sometimes, it's not even something the host can control (network outages).

It's just something that happens, and you have to be able to manage it effectively. When your server goes down the first thing your customers will do is type in your URL and head for the kill.

If your website is hosted on that same server, you end up leaving your customers high and dry to brew.

As a general practice I keep my company website on a server that isn't used very much, in the unfortunate event there is a server outage (which by the way hasn't happened yet :p), the customer can have the comfort of mind that it's being worked on.

I have yet to come across a business that makes money by the second, or even by the minute. If you feel like your entire business is going to crash and burn from a few hours of downtime, perhaps you need to restructure a bit or pay to have your server managed by techs 24/7 if your business is that important.

//End Rant.
 
Will I guarantee it? It's impossible for anyone to guarentee that your server will stay up, in fact in six years of hosting I have yet to be on a host that's not had some downtime.
In a way, I like your approach. Customers too often think that the stated uptime uptime guarantee is the worst case scenario/worst level of uptime they will have, and hosts take advantage of this, when in fact the guarantee is simply monetary.
 
ldcdc said:
In a way, I like your approach. Customers too often think that the stated uptime uptime guarantee is the worst case scenario/worst level of uptime they will have, and hosts take advantage of this, when in fact the guarantee is simply monetary.
That infers, though, that the monetary aspect is only at a customer level. Companies push the envelope on uptime guarantees for two main reasons:

1) Give the clients peace of mind with monetary compensation in the event of an outage that brings the SLA in to place.

2) Keep their internal cogs turning as efficiently as possible. It's an unfortunate fact of life that people work harder when money is on the line. An SLA that puts the company's money on the line guarantee's a few things:
1. When a tech is working on something, no matter how big or small, they take that much extra care.

2. When choosing a datacenter or NOC, a company will choose more wisely, research that little bit more, push floor staff to work with more care and accuracy, etc.

3. Usually, there's an internal opposite of the public SLA. I know at least 20 other companies that operate under this policy: For every month that there isn't a issue that results in the company shelling out cash/credits to the clients, the techs get a bonus of 10-20% (the highest I have heard of is 40%) on their assigned client pool.

An SLA is more than skin deep. It's very important to realise that the public offering is just the beginning, in many cases, of a deep-rooted policy that forms many other policies within the company.


Simon
 
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