Marc Hughes

I am a developer from a bit west of Boston.

Amazon EC2 - SLA available

24 Oct 2008

Today, Amazon EC2 went from beta to a released service and with it they have implemented a service level agreement (SLA). It's not the best SLA I've seen, but it's a start.  The gist of it is:  If, over a year the service drops below 99.95% available then you're entitled to a 10% refund of that year.

          <p>Obviously there's a few problems with that.</p>
            <li>99.95% isn't the best uptime.&#160; I would have liked to have seen at least 99.99%&#160; But for many applications, it probably will be an acceptable amount of downtime.&#160; Add the fact that you have the possibility of hosting in multiple availability zones, and you can mitigate the risk fairly effectively. </li>
            <li>You either have to be a customer for an entire year before you get any redress for 99.95%.&#160; OR they have to have such terrible uptime that it becomes statisitcally impossible for them to hit 99.95% for that year. A per-month SLA would have been better. </li>
            <li>A 10% credit is pretty meager.&#160; But at least it's for the entire period and not for the downtime amount.&#160; This means if I spend $200 a month for a year, they  hit 99.94% uptime, I get a $240 credit.   But that's it.&#160; If they're at 90% uptime I get the same credit.&#160;</li>
        <p>I think this SLA will  help with convincing business folks that EC2 is a viable service, but probably not so much to actually help mitigate damages.</p>
          <p>Compared to the <a href="">google apps SLA</a>, it's a lot better.&#160; It'll be interesting to see how the Google App Engine SLA turns compares when they implement one. <br />