Service-level agreements (SLA) were designed to give cloud users a reasonable amount of assurance that their cloud services would be reliable and have consistently good uptime. But are SLA’s really as good as they seem?
Cloud computing has revolutionized the web hosting industry, making it easier than ever for individuals and organizations to get production-quality web applications or even entire platforms up and running quickly and easily. Nevertheless, there has always been a danger associated with the cloud. Once you turn over operations to a cloud provider, what guarantee do you have that the service will be reliable and that your websites will be available most of the time? An SLA is meant to be the answer to this dilemma.
Ideally, your SLA will guarantee a certain amount of uptime (often 99.99% or something close to it) and offer compensation in the form of credit if the service does not meet that guarantee over the course of a month or other specified period. Before you sign on the dotted line, however, you may want to consider these issues:
- Availability – 99.99% availability over the course of a month is different than 99.99% availability over a year’s span. How? If your provider measures based on the latter, you may have large chunks of downtime in one month but not even know about it until it is calculated at the end of the year
- Scheduled downtime – Is scheduled downtime actually covered in the uptime clause? You better read the fine print.
- Detection – Who is responsible for detecting down time? If it is up to you, will you even notice nightly downtime if you have a small business? Also, how much time will pass between the time you report the downtime to the provider and the time when the clock starts counting the minutes?
These are all issues you should consider before signing an SLA. You should also look at the track record of the provider to see how it handles situations when customers feel the uptime guarantee has not been met. The last thing you want is to end up in court over the breach of an SLA.