RAID Levels

RAID 1

What is another name for hard disk mirroring

Minimum amount of disks for RAID 5?

3

RAID 5

Disk striping and parity and allows for failure of one drive

RAID 0

Performance over redundancy

RAID 0

Sum of all the disks used

RAID 0

Has no redundancy

RAID 1

Data can be Recovered if a drive fails because of mirroring (in this case only because of a perfect mirror)

RAID 1

Half amount of space and slow write performance?

RAID 1

Improves read speed as the data mirrored between two drives

RAID 4

________ stripes the data across multiple disks just like RAID 0. In addition to that, it also stores parity information of all the disks in a separate dedicated disk to achieve redundancy

RAID 4

If the dedicated parity disk fails, data redundancy is lost

RAID 4

The write performance becomes slow because all the parity information is written on a single disk which is a bottleneck

Minmum amount of drives for RAID 0

2

Minimum amount of drives for RAID 1

2

3

RAID 4 uses how many disks?

Riad 5 needs a minimum of _____ disks?

3

RAID 5

Can lose any disk out of three and restore data (one amount of disk space is lost because all parity data is split between the drives)

One disks worth of space is used up to store redundancy information. It is split across all of the drives used.

RAID 5

RAID 6

Can handle up to 2 failed drives

A minmum of 4 disks is needed to use this array

RAID 6

RAID 6

Each disk has two parity blocks?

RAID 10 (1+0) needs a minimum of _____ drives?

4

RAID 10

Combines the striping and mirroring of two other arrays.

RAID 10

Performance of RAID 0 and redundancy of RAID 1

You can safely lose one drive from each mirrored pair without data loss, but if two drives fail within the same mirrored pair, data will be lost.

RAID 10

Each disk has two parity blocks which are stored on different disks across the array

RAID 6