Database Multiple Choice Questions on “RAID”.
1. Which level of RAID refers to disk mirroring with block striping?
a) RAID level 1
b) RAID level 2
c) RAID level 0
d) RAID level 3
Answer: a
Clarification: RAID level 1 refers to disk mirroring with block striping.
2. Optical disk technology uses
a) Helical scanning
b) DAT
c) A laser beam
d) RAID
Answer: d
Clarification: Redundant Array of Inexpensive Disks.
3. With multiple disks, we can improve the transfer rate as well by ___________ data across multiple disks.
a) Striping
b) Dividing
c) Mirroring
d) Dividing
Answer: a
Clarification: Data striping consists of splitting the bits of each byte across multiple disks; such striping is called bitlevel striping.
4. Which one of the following is a Stripping technique?
a) Byte level stripping
b) Raid level stripping
c) Disk level stripping
d) Block level stripping
Answer: d
Clarification: Block-level striping stripes blocks across multiple disks. It treats the array of disks as a single large disk, and it gives blocks logical numbers.
5. The RAID level which mirroring is done along with stripping is
a) RAID 1+0
b) RAID 0
c) RAID 2
d) Both RAID 1+0 and RAID 0
Answer: d
Clarification: Mirroring without striping can also be used with arrays of disks, to give the appearance of a single large, reliable disk.
6. Where performance and reliability are both important, RAID level ____ is used.
a) 0
b) 1
c) 2
d) 0+1
Answer: d
Clarification: Mirroring without striping can also be used with arrays of disks, to give the appearance of a single large, reliable disk.
7. ______________ partitions data and parity among all N+1 disks, instead of storing data in N-disks and parity in one disk.
a) Block interleaved parity
b) Block interleaved distributed parity
c) Bit parity
d) Bit interleaved parity
Answer: b
Clarification: In level 5, all disks can participate in satisfying read requests, unlike RAID level 4, where the parity disk cannot participate, so level 5 increases the total number of requests that can be met in a given amount of time.
8. Hardware RAID implementations permit _________ that is, faulty disks can be removed and replaced by new ones without turning power off.
a) Scrapping
b) Swapping
c) Hot swapping
d) None of the mentioned
Answer: c
Clarification: Hot
swapping reduces the mean time to repair since replacement of a disk does not have to wait until a time when the system can be shut down.
9. ___________ is popular for applications such as storage of log files in a database system since it offers the best write performance.
a) RAID level 1
b) RAID level 2
c) RAID level 0
d) RAID level 3
Answer: a
Clarification: RAID level 1 refers to disk mirroring with block striping.
10. ______________ which increases the number of I/O operations needed to write a single logical block, pays a significant time penalty in terms of write performance.
a) RAID level 1
b) RAID level 2
c) RAID level 5
d) RAID level 3
Answer: a
Clarification: In level 5, all disks can participate in satisfying read requests, unlike RAID level 4, where the parity disk cannot participate, so level 5 increases the total number of requests that can be met in a given amount of time.