0

I have a relatively old Windows Server 2008 machine that I am upgrading the disk space on. The disk hardware I am upgrading to is:

  • 2TB WD - WD20EARX
  • 2TB Seagate - ST2000DM001
  • 1TB Seagate - ST31000528AS
  • 1TB Hitachi - HDS721010CLA332
  • Spare 500GB WD

One of the key problems is that the motherboard does not have support for EFI, so I'm stuck to MBR partitions. Ideally I'd like to have a RAID5 with (2) 2TB and (2) 1TB drives (yes I know I will only get 1TB out of each of the 2TB drives in this configuration), but Windows throws a disk I/O error when trying to create this, even if I try to only allocate 50MB from each drive.

Edit: Windows will allow me to create a simple RAW partition on either of the 2TB drives, but any size above 1024GB will fail to format the drive.

Windows will show the option to 'Convert Disk to GPT', but this throws the same disk I/O error as above for the 2TB drives. The 1TB drives will convert successfully. Additionally, creating a spanned volume with the 2TB drives at any allocation size attempts to convert the drives to dynamic drives, and has the same failure result.

Windows will allow me to create a spanned or RAID5 volume using the (2) 1TB and (1) 500GB, but if I add either of the 2TB drives into the mix it always has this plain undescriptive disk I/O error.

It seems that any time I try to create any RAID configuration with a 2TB drive Windows doesn't allow it, even with a smaller partition size like I mentioned earlier. I would imagine that I'd be able to use part of the drive at least. Does anyone know why I'm having this problem?

Any input to this would be greatly appreciated!

  • you only need MBR if you are booting from the drive, GPT disks are supported for non-boot regardless of motherboard EFI – Richie Frame Jun 23 '15 at 6:44
  • another reason you may get weird undescriptive errors is if the logical sector size of the disks do not match, ie, the 2TB drives are advanced format. – Richie Frame Jun 23 '15 at 7:11
  • @RichieFrame Can you tell me more about the logical sector sizes? I thought the OS defines the sector size when creating the partition. Wouldn't Windows set the sector size of all 4 unallocated drives to the same size when creating the RAID? I have added the model IDs of the HDDs to the original post. – BarryBostwick Jun 23 '15 at 14:07
  • Don't be using R5 anyway please, it's 2015, it's of no/little use these days. – Chopper3 Jun 23 '15 at 15:40
  • @RichieFrame Also in regards to your first comment, the GPT option isn't available for the non-boot drives according to the Disk Management utility in Windows Server 2008. It appears grayed out. Any idea why this would be? – BarryBostwick Jun 23 '15 at 15:42
0

As far as I remember Windows software RAID refuses creating an array on disk with different block sizes (limitation), are you sure that your disks' block size are equal? I can bet that 2TB disk has 4096 bits sector and 1TB 512 bits.

  • Can you tell me more about the block sizes? I thought the OS defines the block size when creating the partition. Wouldn't Windows set the block size of all 4 unallocated drives to the same size when creating the RAID? I have added the model IDs of the HDDs to the original post. – BarryBostwick Jun 23 '15 at 14:21
  • Michal, I made a modification to my original post. The edit is in bold. Does this add any insight into the problem? Any help is greatly appreciated. Thanks! – BarryBostwick Jun 24 '15 at 0:08
  • Have you found physical sector size? Block size ( physical sector size) - minimal allocation space on hardware layer, file system block size (minimal allocation space on software layer, sometimes called by cluster size, NTFS minimal allocation unit) – Michal Sokolowski Jun 24 '15 at 13:49
  • WD20EARS has 4096, ST2000DM001 has 4096, ST31000528AS has 512, HDS721010CLA332 has 512, that's your problem. – Michal Sokolowski Jun 24 '15 at 13:52
  • You should be able to create raid 1 (MBR, on dynamic disks) between those two 2TB drives. – Michal Sokolowski Jun 24 '15 at 13:57

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.