RAID Technology – 1

This set of multiple choice SAN storage questions and answers focuses on RAID technology and various levels of RAID.

1. Which of the following is correct about hardware RAID controllers?
a) Volume management is performed by the server
b) Volume management is performed by controller card
c) Dedicated cache memory decreases server write performance
d) Parity calculation by the server and cache memory in the RAID controller increases read and write performance

2. Which RAID type doesn’t use parity for data protection?
a) RAID 1
b) RAID 4
c) RAID 6
d) RAID 5

3. Which one of these is characteristic of RAID 5?
a) Distributed parity
b) No Parity
c) All parity in a single disk
d) Double Parity

4. What is the unique characteristic of RAID 6 (Choose one)?
a) Distributed Parity
b) Striping
c) Two independent distributed parity
d) Mirroring

5. Which of the following combinations can support RAID 05?
a) 2 sets with 3 disks each
b) 3 sets with 2 disks each
c) 2 sets with 4 disks each
d) 4 sets with 1 disk each

6. What is the minimum number of disks required for RAID1?
a) 1
b) 2
c) 4
d) 5

7. Which of the following raid levels provides maximum usable disk space?
a) RAID 1
b) RAID 0
c) RAID 5
d) RAID 6

8. Can you help decide on the RAID level to use – we are a media house and we use lot of graphics/video applications – we need large throughputs for videos to get played without any jitter and since we are in publishing business we can’t afford downtimes.
Even if there is any downtime we would like our data to be quickly reconstructed and enable us to continue with out work in less time
a) Raid 5
b) Raid 10
c) Raid 6
d) Raid 01

9. The mean time to failure of a single disk is 200000 hrs. If an array of disks is using 5 such disks, the mttf of the array is
a) 200000 hrs
b) 40000 hrs
c) 1000000 hrs
d) Can not be determined

10. An array of disks is more likely to fail compared to a single disk. How is it that RAID arrays still manage to provide more data protection compared to a single disk?
a) Using either mirroring or striping
b) Using either mirroring or parity
c) Using better quality disks
d) Using dedicated hardware