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We are going to take a closer look at RAID 0 also known as striped drives

How does RAID 0 work?

The requirements are that you have a minimum of 2 hard drives. You can have several hard drives in one array, and what it does is that the RAID controller joins all the hard drives into one big virtual drive. So if you have 4 hard drives instead of having 4 different logins or stations and you have to move data and remember on which station or volume is for your movies and which station or volume is for your pictures and stuff like that.

Advantages of RAID 0:

You have an increased Reading and Writing speed. An example of 2 hard drives in RAID 0 will perform much much better than a single drive.

 

 

So instead of having one drive of may be 1TB if you have two 500GB drives you will get 1TB storage capacity, but the reading and writing speed will be much higher. And the reason why is, with 1 single drive you are limited to speed between the hard drive and mother board by disk controller. Let’s say for example this is 100MB/sec. If you have the two 500GB drives on two separate disk controllers each hard drive is capable of reading or writing 100MB/sec, and when the RAID controller gets the data from the operating system to write it to the drives it writes to both at the same time. Thus you get this combined speed of each drive and that would mean up to 200MB/sec instead of 100MB. Of course you can strip several hard drives together, and if you have 5 hard drives on independent controllers you will be able to read and write up to 5 times speed of a single drive. So if you have something that is really hardest in terms like video editing, may be photo editing and stuff like that music recording you’ll really benefit from the increased read and write speed.

The disadvantage with a RAID 0 on stripped array is that it offers no redundancy. How then could it be a RAID array; it is actually not, but the RAID 0 architecture is included in RAID terminology because it requires RAID controller to do the work. So it’s not true RAID but must be counted as a RAID.

Here is an example of 2 disk array with each having 1TB of capacity. We have our RAID controller if there’s software based or hardware based, and we have these virtual disks that are presented to the operating system and as you can see its 2TB. So you have 2 hard drives and operating system only sees one big drive of one station or one volume. That’s thanks to RAID controller.

HDD #1 (1TB)

HDD #2 (1TB)

Virtual HDD (2TB)

 

 

 

 

 

RAID

 

 

 

 

 

 

 

 

 

 

 

Now we’re going to take a look at how data is been written and also it would be the same principle of reading from the volume. First of all we have set of bits here which is only 8 bits. It is simplified just to show you the principle of how it works. The operating system wants to write this 8bits to hard drive.

HDD #1 (1TB)

HDD #2 (1TB)

Virtual HDD (2TB)

 

 

10101010

 

 

RAID

 

 

 

 

 

 

 

 

 

 

 

What the RAID controller will do is take the first half of the data and write it to the first hard drive. Then it will take the second part of the data and write is to the second hard drive. It would keep doing this all the time and it will give you increased speed working like a charm until hard drive fails.

HDD #1 (1TB)

HDD #2 (1TB)

Virtual H

DD (2TB)

1010

 

1010

1010

 

 

RAID

 

 

 

 

 

 

 

 

 

 

 

 

 

 

HDD #1 (1TB)

HDD #2 (1TB)

Virtual H

DD (2TB)

1010

1010

1010

1010

 

 

RAID

 

 

 

 

 

 

 

 

 

 

 

 

 

 

HDD #1 (1TB)

HDD #2 (1TB)

Virtual H

DD (2TB)

1010

1010

1010

1010

1100

1100

RAID

1100

1100

1001

1001

1001

1001

1110

1110

1110

1110

1111

1111

1111

1111

 

What happens in this case when second hard drive fails? First of all the entire data on that drive #2 is no longer accessible. So what would that result in? It actually results in all of your 2TB of data being lost. And the reason for that is that the disk #2 here had all the second halves of the data. Even though disk #1 is alive it only contains half set of each data, and so it’s no longer usable. The result of this is “all your files are gone”, and you have a big problem.