Highly Available and Strongly Consistent Storage Service Using Chain Replication | Kumar Mrinal & Binbin Lu – In this talk, we present Dumbo – a simple, reliable, highly available, low dependency object storage system that powers Meta’s build and distribution infrastructure. Dumbo is designed to be extremely simple and have minimal dependencies so as to cater to critical package workloads. This is vital to ensure a seamless disaster recovery and bootstrap strategy. Dumbo leverages chain replication as an approach to coordinate clusters of fail-stop storage servers. We talk about how this compares to classical quorum based solutions in terms of simplicity, performance, consistency and other relevant considerations. We walk-through our journey from a research-paper inspired prototype solution to a fully functional large scale storage service in production. We discuss the milestones, learnings and key observations along the way. We talk about Dumbo’s evolution which started with supporting Meta’s build infrastructure to positioning itself as a gateway to all archival storages within Meta, thereby facilitating the disaster recovery story for core Meta services. We finally wrap with recent feature advancements in our service like cross region replication, backup and restore, recovery provider as a service.