Solved

What is "RAID" concept ? Why it is needed ? How many types are there ?

Posted on 2007-12-05
7
1,345 Views
Last Modified: 2013-12-18
Hi,

I want to know "RAID" concept. Can you please explain me in SIMPLE terms :

1. What it is ?
2. Why it is needed ?
3. How many types are there ?

with plain english to understand basics easily.

Appreciate your time and patience !!

Thanks
0
Comment
Question by:kishore_peddi
7 Comments
 
LVL 25

Accepted Solution

by:
imitchie earned 168 total points
ID: 20416673
1. What it is ?
It is a way to use multiple DISKS working together as ONE storage system.

2. Why it is needed ?
For redundancy, better performance or both.

3. How many types are there ?
RAID 0, 1, 2,5,5, 10, 50,80,0+1 etc.

Here's a link to read more about it
http://en.wikipedia.org/wiki/RAID
0
 
LVL 9

Assisted Solution

by:FilipZahradnik
FilipZahradnik earned 166 total points
ID: 20416695
RAID technology allows you to use multiple physical harddisks as one logical drive.

There are 2 main reasons why people do this:
- To improve reliability. This is done by having the same data stored on more than one physical disk so that when one disk fails, you still have your data on the other disk.
- To improve performance. This is done by spreading data accross multiple disks and reading/writing to those disks simmultaneously.

There are other more obscure reasons, but redundancy and performance are the main ones.

RAID configurations are described as RAID levels using a number, e.g. RAID0, RAID1, RAID5, etc. Each configuration has different properties and serves a different purpose. Then there are nested RAID levels, where you combine 2 levels, e.g. RAID1+0 (sometimes referd to as RAID10), RAID5+0, etc.

You can read more about RAID and RAID levels here: http://en.wikipedia.org/wiki/RAID
0
 
LVL 13

Expert Comment

by:Wizilling
ID: 20417068
This would help
http://en.wikipedia.org/wiki/RAID

the most common ones are RAID 0, raid 10 , RAID 5
0
 
LVL 18

Expert Comment

by:Yveau
ID: 20422987
On the different types, In a nutshell, best performance in OLTP database systems is RAID 10 ... but that is a pretty expensive as well ... for OLAP 5 turns out to be very good as well ...

and I'm not going to post the link for the fourth time :-)

Hope this helps ...
0
 
LVL 22

Assisted Solution

by:dportas
dportas earned 166 total points
ID: 20429964
Everything you need to know about RAID5: www.baarf.com
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

If you have heard of RFC822 date formats, they can be quite a challenge in SQL Server. RFC822 is an Internet standard format for email message headers, including all dates within those headers. The RFC822 protocols are available in detail at:   ht…
In this article I will describe the Backup & Restore method as one possible migration process and I will add the extra tasks needed for an upgrade when and where is applied so it will cover all.
This video shows, step by step, how to configure Oracle Heterogeneous Services via the Generic Gateway Agent in order to make a connection from an Oracle session and access a remote SQL Server database table.
This video shows setup options and the basic steps and syntax for duplicating (cloning) a database from one instance to another. Examples are given for duplicating to the same machine and to different machines

816 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

8 Experts available now in Live!

Get 1:1 Help Now