LaCie Biggest Quadra

Understanding RAID

User Manual

page 19

 

 

3.4. RAID 5 + Hot Spare

This level is the same as RAID 5, but one disk is des- ignated as a “Hot Spare,” which means that in the event of a disk failure, the “Hot Spare” disk would automatically be activated to replace the failed disk.

The storage capacity of a RAID 5+ Hot Spare array fol- lows the same logic as that of RAID 5, but with the dif- ference being that there is one less disk in the array. So, for instance, if there was a RAID 5+ Hot Spare array with three drives of varying capacities of 40GB, 50GB and 60GB, and one disk designated as the hot spare with a capacity of 70GB,

This diagram represents a

ERAID 5 array, consisting of

D

four disks, which are

C

connected to the Controller.

Parity blocks are represented

B

by the letter P.

A

 

CONTROLLER

the total capacity of the array would be 80GB [2 (3 disks – 1 disk) x 40 = 80].

A

B

PAB

C

PCD

D

PEF

E

F

G

H

PGH



"

/

-

*



,

Fig. 3.4.

Page 20
Image 20
LaCie FIREWIRE 800/400 user manual RAID 5 + Hot Spare