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AWS outage - It wasn't just DNS

The AWS outage that temporarily took down so much of the Internet this week has been reported as being due to a DNS issue, but that wasn't the root cause.

AWS have posted details of the incident that explains how a race condition in the mechanism in place for updating the DNS records ultimately caused the problem.

I suspect that the possibilty of the race condition occurring may have been increased by changes required for the use of IPv6 for DynamoDB, as that would have involved expanding the amount of data involved.

It will be interesting to see if AWS offers up more details of their approach to eliminating the race condition. As much as anything, I'm curious to find out what is similar to the race condition that I worked through earlier this year.

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Location: Christchurch, New Zealand

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