Computer and Software Support


Raid advantages and disadvantages

For an explanation of what RAID is, click here

 

Advantages of Striped RAID

Striped is used for speed. What striped RAID does is it writes to both hard drives at the same time. For example, RAID will save one part of a document to the first hard drive. While it is saving that part to the hard drive, RAID will be saving the other part of the document to the other hard drive. One hard drive will contain some of the data and the other hard drive will contain the rest of the data. The raid table enables the system to understand the layout so you can retrieve the data later. RAID also does this in reverse, while RAID is retrieving data from one hard drive, it is also getting data from the other hard drive. This speeds up the performance of the system.

 

Disadvantages of Striped RAID

There is no redundancy using Striped RAID. If one of the two hard drives die, your data is lost, unless you manually backed up the data to another location.

 

Advantages of Mirrored RAID

All the data is stored on one of the hard drives, then RAID makes a duplicate copy of that hard drive to the second hard drive. This provides redundancy in the event a hard drive dies. When you have a hard drive failure, you replace the bad hard drive, and RAID will copy the image of the other hard drive to the new hard drive. Very good tool for data protection against hardware failure.

 

Disadvantage of Mirrored RAID

Not as fast as Striped RAID. This is a good backup for hardware failures, but does not protect you from software issues such as corruption or a virus. If your system gets hit by a virus that damages your files, your files are going to be damaged on both drives. Therefore your data will be lost unless you have manually backed up the data to another source such as a DVD or external hard drive.

 

NOTE: There is raid configurations that use both Stripe and Mirror, however it increases the cost of the RAID configuration.

NOTE: using RAID increases your cost of the system because it requires a minimum of two hard drives for RAID 0 and RAID 1. Other RAID configurations require 3 or more hard drives and that increases the cost of the system.