F i g u r e 2 - 4 . E x a m pl e o f Par i t y

Parity

Generator

Hot Spares

A hot spare is an extra, unused disk drive that is part of the disk subsystem. It is usually in standby mode, ready for service if a drive fails. Hot spares permit you to replace failed drives without system shutdown or user intervention.

PERC 3 implements automatic and transparent rebuilds using hot spare drives, providing a high degree of fault tolerance and zero downtime. The PERC 3 RAID management software allows you to specify physical drives as hot spares. When a hot spare is needed, PERC 3 assigns the hot spare that has a capacity closest to and at least as great as that of the failed drive to take the place of the failed drive.

Introduction to RAID

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Dell 3 manual Hot Spares, G u r e 2 4 . E x a m pl e o f Par i t y