Amazon.com, Inc.
Hierarchical authority store for cross-zone replicated block storage devices

Abstract:

The present disclosure generally relates to creating virtualized block storage devices whose data is replicated across isolated computing systems to lower risk of data loss even in wide-scale events, such as natural disasters. The virtualized device can include at least two volumes, each of which is implemented in a distinct computing system. Each volume can be implemented by at least two computing devices, a first of which is configured as a primary device to which reads from and writes to the volume are directed. To ensure consistency in the distributed device, a multi-tier authority service is implemented, in which a cross-computing system authority service designates a volume as having authority to accept writes to the virtualized device, and in which a second tier authority service designates a computing device as having authority to accept writes to the volume.