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Congratulations! You survived the leap secondocalypse

Tweets mistimed, AWS outed, yet world somehow continues turning. Albeit more slowly

The leap second did not break the internet, it wasn’t the second coming of the Y2K bug and nor did it challenge the world’s financial markets or make the Greek situation any worse.

Neither did it kick, Netflix, Instagram or Pinterest offline.

At most, the addition of a leap second to Universal Co-ordinated Time (UTC) on Tuesday night seemed to confuse Android phones and their users' diary alerts.

Also, Twitter seemed to have problems knowing exactly when Tweets had been posted.

Mostly, however, it was business as usual – as The Reg predicted it would be here.

There were some problems.

Drew Perttula Tweeted:

Tim Heckerman also Tweeted:

But some intense and desperate Twitterverse analysis determined to hang a 40 minute outage and slow down at Amazon, Instragram, Pinterest and Netflix on the inability of systems to swallow the extra second proved just that. Desperate.

Netflix, Instagram and Pinterest all run on AWS and Amazon had gone to elaborate lenghts to successfully introduce the leap second to the clocks on the servers behind AWS.

AWS runs on Linux, so given the past existence of a date bug in the kernel and the fact Linux swallows the leap second by rolling the clock back to 00.59, the scene was amply set for a story of trial and failure in trying to cope with the leap second.

But the cause was not the leap second, but rather an accident of timing – an “internet connectivity issue” with a provider outside Amazon's network was compromised.

“The root cause of this issue was an external internet service provider incorrectly accepting a set of routes for some AWS addresses from a third-party who inadvertently advertised these routes,” Amazon said.

That is not to say all is sound with the concept of leap seconds.

As The Reg revealed earlier this week, the World Radiocommunication Conference will meet in November to discuss ending the leap second, finally decoupling UTC – based on an atomic definition of the second – from astronomical time, based on the rotation of the earth and flawed by the fact that rotation is slowing.

But in light of this week’s non-event, the chances of the leap second surviving have been vastly improved, especially given the outcome the last time the topic was debated in 2012. The time lords couldn't reach a decision, so kicked a vote on ending the leap second down the road – to November this year. ®

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