RAID 10, also known as RAID 1+0, is a nested RAID configuration that implements a "stripe of mirrors" architecture. It requires a minimum of four drives and combines the data redundancy of mirroring with the performance scaling of striping. This setup provides a robust balance between high speed and fault tolerance without parity overhead.
How it works
The system first mirrors data across pairs of drives (RAID 1) and then stripes data across these mirrored sets (RAID 0). If one drive in a mirrored pair fails, the array remains operational because the data is still available on the partner disk. However, the simultaneous failure of both drives in the same mirror set results in total data loss.
- Minimum drive count: 4 (must be an even number).
- Storage efficiency: 50% of the total raw capacity.
- Performance: Excellent for both random read and write operations due to parallel data access across all drives.
RAID 10 is the standard choice for transactional databases and I/O-intensive production environments. Unlike RAID 5 or 6, RAID 10 does not suffer from a "write penalty" because it does not calculate parity bits during write cycles. This ensures consistent low latency and high throughput even under heavy concurrent write loads.