Can you Raid a Raid?

FallenPhoenixRA · March 3, 2018

Ok so I currently have 2 500 Gb HDDs in raid 0. Those are almost out of space so I ordered a 1 Tb HDD. Can I raid the 2 500 Gbs with the 1 Tb since they are effectively 1 Tb together?

rio2 · March 3, 2018

I really hope that you are not storing any important data on a RAID0 array, because if one of your disks die you will lose all your data. And yes you can in theory do it (it's possible under Linux), but I'am not familiar with raid under Windows if you're running that, but please don't do it for storing anything except easily replaceable data such as programs and an OS as you will have 3 points of failure and if one of your drives die you will lose all your data.

CaseyMazur · March 3, 2018

Correct me if I'm wrong, but can't you just RAID 0 all three drives?

rio2 · March 3, 2018

4 minutes ago, CaseyMazur said:

Correct me if I'm wrong, but can't you just RAID 0 all three drives?

No, because RAID0 relies on striping all data equally on all disks in the array.

Here is a simple illustration on how it works with two drives.

EDIT: you can put two 500Gb and 1TB drive in RAID0, but you wouldn't be able to use the second half of your 1TB disk or you could in theory divide up your 1TB disk into two "500GB volumes" and than put those into the RAID, but I don't know if there is any software support for that.

minibois · March 3, 2018

In what way do you want to RAID them together?

As far as I know, with three drives you could realistically only attempt Raid 10. Which is a raid 0 with two drives (two drives working together, to create 1 bigger and faster drive; but with twice the dangers of losing data), with an added third drive which is a copy/mirror of said raid 0 array.

I think you are just looking to run your 1TB drive on its own, for an added 1TB of storage.