Data Redundancy in MooseFS

Redundancy is a core feature of MooseFS that ensures high availability, data durability, and fault tolerance across distributed storage environments. It allows the system to continue operating correctly even in the presence of hardware failures, such as disk crashes or entire Chunkserver outages.

MooseFS achieves redundancy through two primary mechanisms: copy-based replication and erasure coding (EC). Both methods are configurable via Storage Classes, allowing administrators to define how many failures the system should tolerate and how data should be restored if parts of it become unavailable.

This chapter briefly explains how redundancy is implemented in MooseFS, how to calculate the number of tolerated failures (known as the Redundancy Level), and how to choose between copy format and EC format depending on performance, storage efficiency, and risk tolerance.

Whether you're designing a system for maximum resilience or optimizing for storage cost, understanding redundancy in MooseFS is essential for building a robust and scalable deployment.