On August 31st, 2019, an Amazon AWS US-EAST-1 datacenter in North Virginia experienced a power failure at 4:33 AM, which led to the datacenter’s backup generators to kick on. Unfortunately, these generators started failing at approximately 6:00 AM , which led to 7.5% of the EC2 instances and EBS volumes becoming unavailable. ‘1:30 PM PDT At 4:33 AM PDT one of ten data centers in one of the six Availability Zones in the US-EAST-1 Region saw a failure of utility power.
Our backup generators came online immediately but began failing at around 6:00 AM PDT. This impacted 7.5% of EC2 instances and EBS volumes in the Availability Zone. Power was fully restored to the impacted data center at 7:45 AM PDT.
By 10:45 AM PDT, all but 1% of instances had been recovered, and by 12:30 PM PDT only 0.5% of instances remained impaired. Since the beginning of the impact, we have been working to recover the remaining instances and volumes. A small number of remaining instances and volumes are hosted on hardware which was adversely affected by the loss of power.
We continue to work to recover all affected instances and volumes and will be communicating to the remaining impacted customers via the Personal Health Dashboard. For immediate recovery, we recommend replacing any remaining affected instances or volumes if possible.’