Dictionary · Certification Terminology

A way of combining disks for speed, capacity, or the ability to survive a disk failure. Different levels make different tradeoffs, and none of them replaces a backup.

Mirroring keeps a copy on a second disk. Striping spreads data for speed but can make a single failure fatal. A parity level can rebuild one failed disk. You still need a backup for deletion and malware.

Example: A mirror pair keeps serving data after one disk dies. The array is degraded until the disk is replaced and rebuilt.