What is all this RAID stuff?

[jblondi]

Ive been hearing lots about setting up a RAID. I have no clue really to what it is. Can anyone explain to me how to set up a simple raid, the pros and cons, and what it can do for me. Thanks.

 

[Techwhore]

RAID is the process of using multiple drives as one. There are several arrays.
RAID 0 - Combines two drives so that they are one, increases read/write speed of drives and gives you the capacity of both drives in one.
RAID 1 - is mirroring, two drives, one acts as the data storage drive, the other has the same exact info on it, but is only used as a backup (if u take the first one out or the first one is damaged, nothing will be lost)
RAID 5 - Three or more drives acting in a cycle of backing up and combining. (if you have 4 drives, two will become one and the other two are a mirror of the first two)

For most home users, a raid 0 array is best, it increases read/write performance as well as storage capacity. It is also the most practical seeing as how most of us do not have data of critical importance. I believe you can RAID any two drives regardless of brand, size or model but for best results it's good to use two or more of the same exact drive

 

[Gunbuster]

Warning snide comment follows:

Ive been hearing lots about this forum search function.

 

[Pretender]

<< Ive been hearing lots about this forum search function. >>


Normally I'd agree, but he's asking more of a FAQ-ish question, and most of the RAID posts are with individual problems with RAID, which probably wouldn't help.

 

[andri]

Techwhore - youve got this RAID5 thing wrong. What you described is RAID 1+0, or RAID 10.

RAID5 array size will be size of smallest disk multiplied by number of drives minus one (e.g. capacity=smallest*(count-1) ).
One disk will be used to store checksum etc. information, so if one drive is lost the array can rebuild itself.

For example:
1) eight 9.1 GB hard drives in RAID5: 9.1*(8-1)=9.1*7=63.7GB
2) 800MB, 600MB, 1.5GB, 30GB in RAID5: 600*(4-1)=600*3=1.8 GB

IMHO RAID doesn't offer anything to the average home user.

 

[SUOrangeman]

Who wants to be average anymore? That's why most of us are here in the first place!

-SUO, techie guinea pig

 

[Davegod75]

on my promise controller is says i'm using 2+0 raid? I could of sworn i set it up as raid 0 though. anyone ever heard of raid 2+0?

 

[Techwhore]

thanks for correcting me, andri. I was thinking I had describe 0+1 but wasn't sure so left it as is. Now I understand it better