An Isilon cluster is designed to continuously serve data, even when one or more components simultaneously fail. OneFS ensures data availability by striping or mirroring data across the cluster. If a cluster component fails, data stored on the failed component is available on another component. After a component failure, lost data is restored on healthy components by the FlexProtect proprietary system.
Data protection is specified at the file level, not the block level, enabling the system to recover data quickly. Because all data, metadata, and parity information is distributed across all nodes, the cluster does not require a dedicated parity node or drive. This ensures that no single node limits the speed of the rebuild process.