Both of my RED drives are bundled to controller

I bought 2 WD RED 3TB drives. I want to use them as RAID1. But I discovered an annoying bug: the drives are bundled to a controller, wich means. If I connect the drive to any controller, the drive is uninitialized. If I partition the drive, all seems fine. But if I connect the drive to another controller at the same computer, the drive is again uninitialized. So I played around to see where the problem is caused by. I used other drives at those controller and discovered no problems at all. So it must be the RED 3TB drives…

Question to you is
Do you have 2TB RED drives an get the same behaviour?
Do you have my 3TB drives an get the same behaviour?

Thanks in advance

Every RAID setup has metadata that records information such as stripe size, etc. These metadata could be stored on the drives themselves, or in flash memory on the RAID controller.

ISTM that when you switch drives these metadata may lose their association. But then you say that other drives do not exhibit the same problem … ???

Thanks for your answer.

Ok I see, I have to explain a bit more :wink:

I don’t expect that I could use a drive from i.e. RAID5. But from RAID1 what is only a mirror - and here I tested with several HDDs that my assumption is correct to use a drive from RAID1 at some controller and can access the data.

At my tests I didn’t use RAID!

I simply tried to connect my drive to a controller without any RAID. Then I partitioned the drive and connected this drive to another controller and I saw that the drive was uninitialized :open_mouth:

This behaviour is only at my 3TB RED dirves (I don’t own a 2TB RED), but I can confirm that my 2TB green doesn’t show this behaviour…

Do you own a RED one?

I don’t have any RED drives, but I’m wondering whether you are seeing a problem with the way the two controllers (or their drivers) handle the 2TiB boundary.

When you initialise a drive, you write the partition information to sector 0. I’m wondering whether one controller writes to sector 0 while the other writes to sector 2TiB + 1.

I would use a disc editor to examine both sectors on each of your 3TB drives. The (2TiB + 1) sector would be 0x100000000 in hexadecimal or 4294967296 in decimal.

DMDE (DM Disk Editor and Data Recovery):

Roadkil’s Sector Editor:

HxD - Freeware Hex Editor and Disk Editor:

You could also use DMDE to automatically Search for Special Sector -> Partition Table Sector.