Good to see an analysis emphasizing the metastable failure mode in EC2, rather than getting bogged down by the DNS/Dynamo issue. The Dynamo issue, from their timeline, looks like it got fixed relatively quickly, unlike EC2, which needed a fairly elaborate SCRAM and recovery process that took many hours to execute.

A faster, better-tested "restart all the droplet managers from a known reasonable state" process is probably more important than finding all the Dynamo race conditions.