What is the usable disk space of a RAID 5 array of five 18GB drives with one drive dedicated as a
spare?
A.
18GB
B.
36GB
C.
54GB
D.
72GB
E.
90GB
Explanation:
See http://en.wikipedia.org/wiki/RAID
RAID5 capacity is available disks – 1. 5 disks – 1 – 1 spare = 3 disks. 3 x 18 = 54
it means RAID 5E (parity+spare)
0
0
54
0
0