Windows Azure Leap-Year Glitch Takes Down G-Cloud

Microsoft says that most services have now returned to normal after a day of chaos

Microsoft has confirmed that a service outage that affected its cloud computing service Microsoft Azure, appears to be caused by a leap year bug.

The Government’s G-Cloud CloudStore was among the sites affected by the outage, which Microsoft says has mostly been rectified.

Leap Year Bug

“Yesterday, 28 February, 2012 at 5:45 PM PST Windows Azure operations became aware of an issue impacting the compute service in a number of regions,” wrote Bill Laing, corporate vice president of Server and Cloud at Azure in a blog post. “While final root cause analysis is in progress, this issue appears to be due to a time calculation that was incorrect for the leap year.”

“Once we discovered the issue we immediately took steps to protect customer services that were already up and running, and began creating a fix for the issue,” he explained. “The fix was successfully deployed to most of the Windows Azure sub-regions and we restored Windows Azure service availability to the majority of our customers and services by 2:57AM PST, 29 February.”

Laing did concede however that some regions and customers were still experiencing issues and that as a result they may be experiencing a loss of application functionality.

“We are actively working to address these remaining issues,” he added. “We sincerely apologise for any inconvenience this has caused. ”

Government Issues

The Government’s G-Cloud CloudStore, which was launched earlier this month, was taken offline due to the problems.

“Power outage on microsoft azure means #cloudstore is temporarily unavailable. Patch being applied so will update when normal service resumed,” said a post on the official G-Cloud twitter account.

However a second message posted at 3:35pm GMT read: “Update on #cloudstore: microsoft are moving us to a different azure install and are confident we’ll be up and running again by 4pm

This is not the first time that Azure has gone offline. In March 2009, an outage left users unable to access the early test applications. This latest incident is unlikely to inspire confidence in IT managers still recovering from the Amazon Web Services (AWS) outage that occurred last April.

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