Which raid do I use?

[dbrimberg]

I'm not even sure this can be done or not...I want RAID 0 speed over two drives, but I also want a mirror of it like RAID 1 does?

Like disk1-2 stripped and disk 3 a mirror or 1-2? I saw there RAID 0+1 but not sure if that does this, is there a way for this to be done?

 

[boonality]

I believe the correct terminology would be RAID 10 (popularly called raid 0+1) If your motherboard supports it... have it it, or buy a RAID controller card, then have at it. But my question is why? If this is a home/gaming computer, your not going to see a peformance increase at all. If you are constantly moving huge 1+GB files around or something, then it COULD be worth it. But it's generally easier to have a RAID 0 scratch drive and a mirror for your important data.

 

[TechnoPirate]

By the sounds of it, you do want either Raid0+1 or 1+0 (From personal experience I would recommend 1+0, but either should do what you want).

You will need a minimum of 4 drives along with a controller that supports it. It's a nested RAID array so think of it like having either disk0/1 with a stripe then mirroring those 2 drives onto disks 2/3 or mirroring data on disk 0/1 and striping each one to 2/3 (just depends which type (0 or 1) is the parent type of the nested array.

Hope this helps

 

[dbrimberg]

But it's generally easier to have a RAID 0 scratch drive and a mirror for your important data.

Yeah that is what I wanted to do, guess I have my terminology incorrect. Explain this above? RAID 0 scratch drive? How many drives do I need for this set up?

 

[dbrimberg]

I just know there is dataloss under RAID 0, but I wanted the speed of a raid and the reliability of having the data on a mirror drive. I dont know enough about RAID to figure out which I need to use and how many drives.

 

[homerdog]

RAID 5

 

[bliq]

RAID arrays can technically work on partitions, not just disks, so if you had just two drives, you could make 2 partitions on each drive and RAID 0 between drives, and RAID 1 between partitions or something like that, but then you lose the speed because you don't have the heads to do each operation independently.

You really need to run 4 drives to get the maximum speed AND fault tolerance. If it's not an option, get most of the speed and fault tolerance with RAID 5, with 3 drives. You lose some speed due to overhead of writing parity information and the fault tolerance results in degraded performance while rebuilding the failed drive, compared to no degradation with R1+0.

 

[dbrimberg]

If it's not an option, get most of the speed and fault tolerance with RAID 5, with 3 drives. You lose some speed due to overhead of writing parity information and the fault tolerance results in degraded performance while rebuilding the failed drive, compared to no degradation with R1+0.

Should the 3 disks be the same size?

 

[halcyon]

I just know there is dataloss under RAID 0, but I wanted the speed of a raid and the reliability of having the data on a mirror drive. I dont know enough about RAID to figure out which I need to use and how many drives.

You could just use the (R)AID 0 (because there's nothing redundant about it) and back up your important data to a 3rd disk using any number of free backup solutions (ie, Version Backup)...or you could indeed set up the (R)AID 0 and then do a RAID 1 mirror.

Here's what I'd recommend though. Spend 10~15 minutes with this link, I think you'll be glad you did and smarter for it: http://en.wikipedia.org/wiki/RAID#RAID_principles

HTH

 

[dbrimberg]

Thanks Halcyon!

 

[halcyon]

No problem, RAID can be confusing but I think that article helps sort it out.