ISC Exam Questions

Which level of RAID is commonly referred to as disk mirroring?

Which level of RAID is commonly referred to as disk mirroring?

A.
RAID 5

B.
RAID 1

C.
RAID 3

D.
RAID 0

Explanation:
Redundant Array of Inexpensive Disks (RAID) is a method of enhancing hard disk fault tolerance,
which can improve performance (see Table A.8). RAID 1 maintains a complete copy of all data by
duplicating each hard drive. Performance can suffer in some implementations of RAID 1, and twice
as many drives are required. Novell developed a type of disk mirroring called disk duplexing, which
uses multiple disk controller cards increasing both performance and reliability. *RAID 0, gives some
performance gains by striping the data across multiple drives, but reduces fault tolerance, as the
failure of any single drive disables the whole volume. * RAID 3, uses a dedicated error-correction
disk called a parity drive, and stripes the data across the other data drives. * RAID 5 uses all disks in
the array for both data and error correction, increasing both storage capacity and performance.