This coming week I'm planning to do my first RAID 0 set up using 2 Western Digital 2TB Caviar Black HDDs, before buying my second WD HDD I just wanted to clarify would the 2TB Caviar Black be acceptable for RAID 0, after reading this quote about it's firmware issue from NCIX I'm starting to have some concerns.
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Hard drives have their own internal controllers, with their own firmware dictating their behavior. 'Consumer' drives use different parameters in their firmware than 'enterprise' drives. One such example is the TLER that every is mentioning in this thread. Basically, 'consumer' drives assume that they're the only disk in a system, so if they're having trouble reading a particular sector, they will try REALLY REALLY hard to fix it before reporting an error to the controller and the OS. In fact, they will try so hard, that it actually looks like the drive has stopped responding completely for a while. While your average SATA controller doesn't care about this, hardware RAID cards do -- if a disk stops responding, it assumes that the drive has failed and will kick it out of the array. This is bad. The 'enterprise' versions of the firmware have timeout values so that instead of trying indefinitely to fix problems, drives report them to the controller much faster, and the controller decides what to do with that information -- perhaps just rebuild the failed sector from parity and remap the failed block.
While I am sure this has some basis of truth to it, I have never, ever heard of this causing any problems.
You can literally use any drive you want in an array, it does not matter at all, they will all work. There are secondary considerations that you take into account depending on the type of array you want, and 1 of those should be a good backup.
While any identical drives will work in a striped RAID configuration, MBR type of partitions handle up to 2 TB of size, so possibly what was being related was drive volumes over 2 TB wont work, and 2 2 TB drives in RAID 0 is 4 TB.
The article is correct, the lack of TLER in consumer drives can be an issue in RAID arrays. The big question is how likely it is to be a problem, and unfortunately I can't really answer that. All I can say is that if you were really concerned about data integrity then you'd be better off with an enterprise-class drive.
But if you're going to use RAID-0 then clearly you're not overly concerned about data integrity so I think it's probably a non-issue for you (although in your place I'd really want to be sure that I had a sound backup strategy).
As far as volumes > 2TB, they should work fine as long as you're using Vista or Windows 7 and you're only using the volume to hold data and not the OS. The issue is that conventional MBR-style partitions max out at 2TB - to go beyond that you need to use GPT-style partitions, and most current motherboards lack the EFI BIOS that's needed to boot from such a partition. But it won't be a problem if you're not trying to boot from it.