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NOTE: Refer to Chapter 11 "PERC 3 BIOS Configuration Utility" for the procedures used to designate a drive as a hot spare.

NOTE: Refer to Chapter 11"PERC 3 BIOS Configuration Utility" for the procedures used to designate a drive as a hot spare.

There are two types of hot spares:

Global Hot Spare

Dedicated Hot Spare

Global Hot Spare

A global hot spare drive can be used to replace any failed drive in a redundant array as long as its capacity is equal to or larger than the coerced capacity of the failed drive. A global hot spare defined on any channel should be available to replace a failed drive on both channels.

Dedicated Hot Spare

A dedicated hot spare can be used to replace a failed drive only in a selected array. One or more drives can be designated as member of a spare drive pool; the most suitable drive from the pool is selected for fail over. A dedicated hot spare is used before one from the global hot spare pool.

Hot spare drives can be located on any RAID channel. Standby hot spares (not being used in RAID array) are polled every 60 seconds at a minimum, and their status made available in the array management software. PERC 3 offers the ability to rebuild with a disk that is in a system, but not initially set to be a hot spare.

Observe the following parameters when using hot spares:

Hot spares are used only in arrays with redundancy, for example, RAID levels 1, 5, 10, and 50.

A hot spare connected to a specific PERC 3 controller can be used to rebuild a drive that is connected to the same controller only.

You must assign the hot spare to one or more drives through the controller’s BIOS or use array management software to place it in the hot spare pool.

A hot spare must have free space equal to or greater than the drive it would replace. For example, to replace an 18 GB drive, the hot spare must be 18 GB or larger.

Disk Rebuilds

You can rebuild a disk drive by recreating the data that had been stored on the drive before the drive failed.

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Introduction to RAID

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Dell 3 manual Disk Rebuilds, Global Hot Spare, Dedicated Hot Spare