I have attempted to preclear a 4tb Toshiba drive. twice. It has failed twice at the exact same stopt. The drive is brand new. Installed it as parity, without preclearing first. After a few hours of parity sync, I would find the disk with a Red X, disabled. It get no useful info in the putty/preclear screen. It just froze, text pasted below.
Also the web ui is inaccessible after the preclear failure, reboot is required to restore. This is anew build with all brand new parts. Log attached device in question is Y5OAKE1QFSAA (sdb) 3907018584.
Disk Temperature: 36C, Elapsed Time: 30:57:43
1907719+10 records in
1907718+10 records out
4000784932864 bytes (4.0 TB) copied, 62088.4 s, 64.4 MB/s
Wrote 4,000,784,932,864 bytes out of 4,000,787,030,016 bytes (99% Done)
unRAID server Pre-Clear disk /dev/sdb
= cycle 1 of 1, partition start on sector 1
= Disk Pre-Clear-Read completed DONE
= Step 1 of 10 - Copying zeros to first 2048k bytes DONE
= Step 2 of 10 - Copying zeros to remainder of disk to clear it
= **** This will take a while... you can follow progress below:
=
Disk Temperature: 36C, Elapsed Time: 30:57:43
1907719+10 records in
1907718+10 records out
4000784932864 bytes (4.0 TB) copied, 62088.4 s, 64.4 MB/s
Wrote 4,000,784,932,864 bytes out of 4,000,787,030,016 bytes (99% Done)
loopcerv-diagnostics-20160309-1904.zip