Microsoft Windows Azure Experiences Outage Due to Leap Day

Microsoft's Windows Azure experienced a service disruption in several regions around the world that began on February 28 from 5:45 PM PST and lasted until 2:57 AM PST on February 29. During this time, the outage left several customers without access to their cloud applications. Microsoft has attributed the outage to a bug related to Leap Day.

Bill Laing, Microsoft's corporate vice president of the Server and Cloud Division, made a statement to explain the outage and Microsoft's efforts to resolve the problem. Here's an excerpt of the statement from Laing:

"We sincerely apologize for any inconvenience this has caused," Laing said. Despite Laing's apology, the consequences of this service disruption could potentially be severe for Microsoft. The outage lasted for eight hours and no official statement from Microsoft had been made up until Laing's statement. In addition, many organizations are hesitant to move to the cloud due to security and outages. Unfortunately for Microsoft, this incident reinforces the idea that instability is a danger that sometimes accompanies the cloud.

Finally, this situation highlights the fact that Microsoft didn't adequately test for this date test-case scenario. Although it might be easy to overlook the Leap Day scenario in a complex system such as Windows Azure, Microsoft developers should have taken care to adequately test this common date scenario in which Leap Day would undoubtedly cause problems for Windows Azure.