Yesterday (July 26th PDT), Windows Azure experienced a service interruption in the West Europe sub-region lasting approximately 2.5 hours.  First, I’d like to apologize for the interruption and the issues it caused affected customers.  The issue has been resolved and all related services are healthy.

The interruption impacted our Compute Service and resulted in connectivity issues for some of our customers in the sub-region.  The service interruption was triggered by a misconfigured network device that disrupted traffic to one cluster in our West Europe sub-region. Once a set device limit for external connections was reached, it triggered previously unknown issues in another network device within that cluster, which further complicated network management and recovery. Our teams are working hard on a full root cause analysis and we will share the findings on this blog next week.

We sincerely apologize for any issues this caused impacted customers, and will make the necessary adjustments to help prevent a similar issue from occurring in the future.  Impacted customers should contact support to file an SLA credit.

  - Mike Neil, General Manager, Windows Azure