I have one of these drives with a strange issue. When put into a RAID 5 array using mdadm, the drive will become confused when data is written to it.
More specifically, I can (and have) written data to it and read it back confirming contents all day. Once the drive isn in an array, it will stop functioning correctly. I can write some data to the array, but the drive will quickly begin returning errors, causing mdadm to kick it out. If it is a complex write (such as filesystem data), the drive will fail out in a matter of seconds. If it is a simple write (just dumping random data into the array from the beginning) it will take longer.
In comparison two other drives with the same model but different sub-model are working perfeclty:
WD20EARX-008FB0
This seems to be a new sub-model; have others had success or similar failure with it? I am trying to decide if i should order a replacement of the same model or look elsewhere.
Do you consider a motherboard’s onboard SATA controller to be a RAID card? It may be easy to assume that just because I am constructing a RAID array that I am using a RAID card, however this is not the case.
The SATA controller is in native AHCI mode, no RAID functionality is enabled. As far as I am aware, there is no hardware RAID controller on the board, just the BIOS-assisted software raid which no-one should use IMHO.
Additionally, the firmware revisions appeared to be the same across all four drives. Do you think that a hardware revision without a firmware revision could have caused this issue, and the drive was indeed faulty?
I am still unsure that RAID-enabled drives will make a difference here. What differences other than TLER are present in, for example, a WD Red branded drive which you seem to be pushing me to purchase?
I know that WD Green drives will like to go to sleep often, however in these tests the drive never had a chance to spin down.
