Cloud Computing: On-Premise versus Cloud uptimes

While having all your applications running in your own data center may give you a better sense of control compared to a scenario where they’re running in the cloud, the uptimes of major cloud players typically exceed the uptimes provided by on-premise applications.

Krishnan Subramanian, principal analyst at Rishidot Research, told Services Angle that “in order to offer compute resources at scale for an affordable price, service providers are going to build their cloud platforms on commodity hardware.  With commodity hardware, outages happen. And at such large-scale, outages will be difficult to manage. So, it is important that apps are developed for cloud architecture keeping this basic nature of cloud in mind. ‘Design for failure’ has to be the mantra for cloud developers.”

Subramanian blames the vendors building services on top of cloud platforms as the true culprits when glitches at cloud providers like AWS ultimately occur.  “Many of the startups are running without a proper DR strategy. It is a shame that some of the well funded startups didn’t bother to plan for such eventualities.”

While media stories blare headlines of failure when cloud provider service outages happen, Subramanian notes that on-premise enterprise downtimes are typically much worse.  He said that “since it [an outage] is  internal and they are responsible for their destiny, it doesn’t get amplified in the media.”  Another IT consultant commented that “Amazon’s such a large target, you just hear about outages more often than you do with large enterprises.”

SearchDataCenter supports that conclusion with anecdotal information from IDC cloud research analyst Rick Villars.  Villars suggests that  while major cloud platform vendors, like Amazon, score availability statistics in the range of 99.95 percent, enterprise data centers often lag behind with availability scores ranging closer to a range of 95 to 98.5 percent.  But Villars notes that interpreting the cloud vendor statistics are complicated because vendors may have multiple data centers and uptimes can be reported by vendors, like Amazon, as regional uptimes as opposed to the uptimes of a particular availability zone.

Beth Pariseau, author of the SearchDataCenter article, calculates that a true uptime number for AWS may be closer to 99.5 percent, compared  the 99.95 percent regional uptime number that Amazon  quotes.  But even so, at 99.5  percent, AWS still handily exceeds the uptimes reported by most internal enterprise IT operations.