Disks with both data and parity in my new setup.

[Tiago Dias]

Hello all,

I've decided to convert my home server to a SnapRAID system, and it's the first time I'm trying this out.

I've got the following hdds:

2x 4TB
1x 2TB
1x 1.5TB
2x 1TB
2x 500GB

From what I understand from the documentation, if I use 2TB of each of the 4TB disks for parity, and all the other disks as data in their entirity, all the raid data (8TB) will have double parity, and there will be 2TB of non-raid data.

Now, what if I add the remaining 4TB as raid data? Am I correct in assuming those 4TB will have only 1 parity protecting them, and the rest (8TB) will remain with 2 parity bits?

Thanks in advance for your response.

[Walter Tuppa]

No, your setup will not work.
Data and parity are not allowed to be on the same physical disk. If this single disc dies, you would loose two parity bits (one from data and one from parity) => if two disc dies you may be not recoverable, since up 3 or 4 bits of parity are missing.