So I installed two 750gb drives that I had sitting around. I precleared both and both passed fine. I don't even have any data on them yet via the array. Anyway, one failed somehow. It won't let me just remove the disk from the array, instead it just says not installed. Now this is odd :

 

[0:0:0:0]    disk    Lexar    JD FireFly      1100  /dev/sda

[1:0:0:0]    disk    ATA      SAMSUNG HD753LJ  1113  /dev/sdc

[1:0:1:0]    disk    ATA      ST4000DM000-1F21 CC52  /dev/sdd

[5:0:0:0]    disk    ATA      ST4000DM000-1F21 CC52  /dev/sdb

[10:0:0:0]  disk    ATA      SAMSUNG HD753LJ  1113  /dev/sde

[10:0:1:0]  disk    ATA      ST4000DM000-1F21 CC52  /dev/sdf

[10:0:2:0]  disk    ATA      WDC WD1500ADFD-0 7P20  /dev/sdg

 

The SDE is working fine and SDC is the issue. Thing is, the three ST4000DM000 drives WERE SDB, SDC, and SDD. The two samsung drives were SDE and SDF. So.... not sure if that's something to worry about. I've restarted the machine a bunch of times and had to remove one drive at a time between boots to find the trouble drive. Not sure if that caused this.

 

I tried to preclear the borked drive but it says:

 

Sorry: /dev/hdc does not exist as a block device

Clearing will NOT be performed

 

Now I don't have an option to check parity either. I'm not sure what I should do at this point.

First don’t worry about the drive letters, it can change when adding more disks, and it’s not important.

 

You cannot preclear a disk assigned to the array, also check name, it would be /dev/sdc not /dev/hdc.

 

If you want to remove the disk from the array you have to do a new config:

 

- Take a screenshot of current disk assignments

- Go to tools and click new config

- Re-assign all disks except the bad one, make sure parity disk is on the parity slot

- If you haven’t written anything to the disk you’re removing select “parity is already valid” and start array

- If you have written to it don’t check that and start array to begin parity sync

 

Did new config, updating parity now just to be on the safe side.

 

Running preclear on the other 750gb hdd to be damn sure it's not going to fail. Tried running preclear on the drive that had an error and got:

./preclear_disk.sh: line 1307: /root/mdcmd: No such file or directory

Sorry: Device /dev/sdc is not responding to an fdisk -l /dev/sdc command.

You might try power-cycling it to see if it will start responding.

 

 

I ran preclear on both disks 2 or 3 times so I'm not sure if this is a false positive or if it's actually borked. Not sure if I can try hot-swapping the drive to see if it'll start responding or if I'll need to reboot the machine after parity is finished.