Neep help with a crashed RAID 5

[DragonsDream]

I have a crashed RAID 5 made up of 6x6TB discs. A few days ago we had a street wide power outage. When my server box rebooted, something happened. I didn't notice until later. Disc 1 failed and the RAID went into degraded mode. I started a repair, which I calculated was going to take 16 hours for the first step. No idea for the second part it does. We were gone for the weekend, so I just let the repair run while we were away. When we got back, disc 1 was found but not initialized, so I initialized it, but as soon as that finished, disc 3 crashed.

Now, disc 3 is showing crashed and disc 1 as initialized but no longer part of the volume so the whole array is crashed. Is there a way to get disc 1 back in to the volume so I can copy off data before redoing the whole setup (testing the drives, et al). With 2 discs not in the volume, it's crashed. with only 1 missing, it should be degraded and I can still access it.

I'm also wondering if it's possible to clone disc 3 and use the cloned disc in the server to get the RAID array back. is this possible? Thanks for any help

 

[DelJo63]

from the wiki

RAID 5 consists of block-level striping with distributed parity. Unlike in RAID 4, parity information is distributed among the drives. It requires that all drives but one be present to operate. Upon failure of a single drive, subsequent reads can be calculated from the distributed parity such that no data is lost. RAID 5 requires at least three disks.

In comparison to RAID 4, RAID 5's distributed parity evens out the stress of a dedicated parity disk among all RAID members. Additionally, write performance is increased since all RAID members participate in the serving of write requests. Although it won't be as efficient as a striping (RAID 0) setup, because parity must still be written, this is no longer a bottleneck.

So, NO you can't clone one drive.

Typically, the raid software has its own recovery software particular to the supplier.

It is also a common mistake to assume RAID does not require backups.