replace one raid 0 hard drive

[Tuan2]

My HPE 590t has 2 hard drives, set up as a pair of disks of a RAID 0. One is dead. I used the low level utility to remove the dead drive from the RAID 0 config. The good drive is still listed as a RAID 0 member disk. How do I put in a new drive, same model,same everything and re-config this new drive as the other half of the RAID 0 configuration to the remaining good drive?

[Huffer · Accepted solution]

You cannot. Once the drives are set up as RAID-0 the data is striped across them. If one drive goes bad the data on the other drive is gibberish. Unless the whole RAID-0 array was backed up or mirrored (that is what RAID-5 is) then the data is lost. Sorry. Backing up is even more important when you have a RAID-0 because you chance of failure is double what it would be with a single drive. 

If all you are asking is how to reestablish RAID-0 with the new drive and the old drive, go into the RAID utility Ctrl-I at boot and first remove the one drive from the array and then reestablish a RAID-0 with the two drives. 

This might be helpful:

http://h10032.www1.hp.com/ctg/Manual/c01330263.pdf

[Tuan2]

Hi,

Perhaps I misunderstood RAID configurations. I thought RAID-0 is mirroring. Thanks for the link. Not sure whats the point of running RAID-0, if it provides no redundancy with twice the failure risk.

[Tuan2]

The doc talked about setting up RAIDs, but nothing about recovery. Do you know whether a doc about recovery exists? Thanks.

[Huffer]

RAID-0 is striping and the benefit is speed. A RAID-0 is significantly faster than a single hard drive. RAID-1 is mirroring and the benefit is redundancy. RAID-5 takes 4 drives and is both striped and mirrored. If the recovery partition was on the RAID-0 drive array that is gone and you would have to get a recovery disk from HP, set up the RAID-0 (or RAID-1) and then reinstall the software to it.  

[Tuan2]

Hi,

You're correct. RAID-0 is striping. RAID-1 is mirroring. So my system came with RAID-0 set up. I found the white paper about RAID config at HP and in there were the definitions of different RAID configurations. I was confused thinking RAID-0 was mirroring. I'm now setting up RAID-1. Thanks again.