Which RAID configuration provides fault tolerance through data mirroring?

RAID 1 is the configuration that provides fault tolerance through data mirroring. In a RAID 1 setup, data is duplicated across two or more drives. This means that each piece of data is written identically to multiple drives, creating a mirror image. The primary benefit of this approach is that if one drive fails, the system can still operate using the other drive(s) that contain an exact copy of the data. This redundancy ensures data availability and protection against hardware failures, making RAID 1 an effective solution for environments where data integrity and uptime are critical.

Other RAID configurations serve different purposes. RAID 0, for example, focuses on performance through striping but offers no fault tolerance since data is spread across multiple drives without duplication. RAID 5 utilizes block-level striping with parity distributed among the drives, which allows for fault tolerance but does not involve mirroring data. RAID 10 combines features of RAID 1 and RAID 0, providing both performance benefits and fault tolerance through mirroring and striping, but the essential characteristic of mirroring is most directly attributed to RAID 1.