Reliability
Reliability Reinvented!
Enabled by its grid architecture and unique redundancy scheme, the XIV system provides unprecedented reliability. These qualities immunize the system against any single failure and reduce the risk of double failure significantly below the standard.
The XIV system achieves its unmatched reliability through various means:- Active-active with N+1 redundancy – All of the XIV system’s disk drives, modules, switches, and UPS units are fully redundant in a revolutionary active-active N+1 scheme, ensuring high reliability and excellent performance.
- 30-minute rebuild time (or less!) for 1 TB drives – The system is designed to minimize the possibility of double disk failure
- Rebuild of real data only – The system performs rebuild on only that data which has been allocated to volumes and actually written
- Self-healing upon module failure – The system self-heals even after failures in components other than disks, including modules. It initiates a rebuild process and returns to full redundancy.
- Consistent performance through any failure – The system maintains the same high performance level through any failure
The XIV storage platform provides unprecedented data protection and availability. All disk drives, modules, switches, and UPS units are fully redundant in an active-active N+1 scheme, ensuring high reliability and excellent performance.
30-minute rebuild time (or less!)
The system uses a revolutionary redundancy scheme, in which each disk is split into small pieces, and each piece is mirrored on a different disk. As a result, when a disk does fail, all disks in the system participate in the rebuild.
After a failure of a 1 TB drive on a fully utilized system, the system is exposed to double disk failure for a rebuild time of just 40 minutes or less. This time significantly reduces (by orders of magnitude) the risk of double disk failure, especially in comparison with other storage systems.
Rebuilds real data only
The XIV system performs rebuild on only that data which has been allocated to volumes and, of the allocated data, only on data that has actually been written. Given that in most scenarios not all capacity is allocated and not all allocated capacity is used, the system's rebuild time is, in practice, much less than 15 minutes. Other storage systems typically perform disk rebuild at the block level, rebuilding the failed disk completely and taking the full length of time this requires.
Self-healing upon module failure
The XIV system employs self-healing even after module failure by initiating a rebuild process and returning to full redundancy. The failed module is replaced only after redundancy has resumed, protecting the system from technician errors.
