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BawA
04-25-2008, 06:52 AM
any suggestions or just normal OS controller is enough for 3X500Gb to be set in RAID5.
as what i found OS handled raids but puts some weight on resources but is it unbearable?

ohh also its possible to have partition among it, right?
if so then what happens to partition in case one drive goes bad on RAID5 ?

EDIT:
found out that controllers are actually a loaders and nothing else, once OS takes charge its the CPU which handles the load not the controller, its hardware RAID which removes the CPU's need not the Controllers.

so correct me if am wrong, no matter what i must have a raid controller.
dont some MOBO's come with a on-board controllers?

also anything else i should know like setup/installation or something to do with BIOS? cuz what i have in mind is i have to plug the HDD and later on windows stage i can setup the RAID levels/modes.

and atlast in case i need a few files say something which wont fit on DVD and i must take the HDD to another computer how would i know on which HDD those file are located so i can remove it.

lynx
04-25-2008, 08:48 AM
Most mobos have built in RAID controllers these days, but not all will handle R5.

R5 has speed advantages when reading, but disadvantages when writing. In normal use you won't notice the disadvantage because it is buffered, but if you are going to do a LOT of disk updates then R5 is probably not what you want - get an extra drive and go for R0+1 instead.

You have to set up the RAID array FIRST. Once you have set up your RAID array, it appears to the system as a single drive - in the case of 3x500GB drives in R5 it would appear as a single 1000GB drive. You can then partition it just as you would any other drive.

As far as the RAID controller is concerned, the partition information is simply data. If you get a drive failure then the system will work with just 2 drives (but slower). When you replace the faulty drive it will be rebuilt with the missing data, which includes any information about partitions.

All the drives are needed to support the RAID array. It works like this:

Drive 1 Drive 2 Drive 3
Block 1 A B P
Block 2 P A B
Block 3 B P A
Block 4 A B P
Block 5 P A B
Block 6 B P A
As you can see, the data and parity is spread evenly across the drives so you can't take a drive out to use it somewhere else.

From the sound of it, you aren't absolutely sure what you want from a raid system. If that's the case my advice would be to keep well away from it until you are sure exactly what you want. Remember that changing to/from RAID or the type of RAID destroys all the data on the drives, so it can be a very frustrating process if you get it wrong.

BawA
04-25-2008, 11:55 AM
tell me something, do i have to set the drives as RAID or i can use them just like any IDE drive?

clocker
04-25-2008, 01:48 PM
tell me something, do i have to set the drives as RAID or i can use them just like any IDE drive?
What?

KiNdZiUs
04-26-2008, 09:33 AM
tell me something, do i have to set the drives as RAID or i can use them just like any IDE drive?

you can use it as IDE, f.e. if you have 3x500GB HDDs you can freely use seperately as C: D: E: drivers and totally 1,5TB, you don't need R5 .. of course if you have data which is important to you and you don't want to lose it in case of HDD failure then R5 is the solution.

lynx
04-26-2008, 04:59 PM
You can use the drives individually.

If possible, disable RAID mode altogether and use it as an ordinary IDE/SATA controller.

If you have to use the controller in RAID mode, configure the drives as JBOD (Just a Bunch Of Disks). The drives may appear to the system as SCSI drives, but you do not need to treat them in any special way.