What Redundancy Techniques Does OBS Use?
OBS uses the erasure coding (EC) algorithm, instead of multiple copies, to ensure data redundancy.
Compared with the multi-copy redundancy, EC delivers a higher storage space utilization while maintaining the same reliability level.
A bucket with single-AZ storage uses the EC algorithm for data redundancy among nodes in one AZ. A bucket with multi-AZ storage not only ensures redundancy for the data among nodes in an AZ, but also across multiple AZs.
Parent topic: Durability and Availability